Spherical Concentric Layer Cake Tutorial

This tutorial will show you the most basic and least equipment-heavy way of baking the concentric layer cake as seen in both the Earth cake and Jupiter cake. You can stop at half way and just make a hemisphere cake, or make two hemispheres and join them into one as in this video.


How big you make the cake is up to you. For the Earth cake I baked the largest layer in a 2 litre pudding basin. As the Jupiter cake one was for a tute and not for a group of people, I only baked it as big as a 1 litre pudding bowl. There’s no other reason why I baked the sphere smaller – you can make it as big or small as you like.

Let’s begin!

Now, as for the equipment required, you will need a set of any three hemisphere tins or bowls that can fit inside one another. Pudding bowls are great for this if you don’t want to buy hemisphere pans, though you may need to trim it to make it round (I’ll show you how to do that). Any oven-proof ceramic bowls will work fine. If you’re using glass as I do, make sure it’s oven safe and heat treated. Some glass bowls will say ‘heat-resistant’ but that only means they won’t explode in your dishwasher.

Baking times will vary based on how big your bowls are. I’ll give you some guides on that, but do keep a careful eye on your cakes and use your inner baking muse to judge cooking times.

You can use any recipe you like for these cakes. For the centre, I recommend a moist recipe as the centre cake does get baked thrice. For the outer recipes, you need to use a buttercake mixture of some type. Any cake that gets you to cream the butter and sugar together at the first step should be fine, as the batter is thick enough so that the cakes won’t sink. Any mudcake, traditional sponge, oil-based recipe or one that melts the butter will probably not hold the weight of the cakes while it bakes.

Lastly, for the colouring you can use any colours you like. Buttercake isn’t delicate, so you can use anything from powder, to liquid, to gel paste. If you’re not sure how much you need, add a little at a time until you’re satisfied with the result. Keep in mind that colours will lighten during baking. You can also make your own colours from things like fruit and vegetable products, and making home made food dyes is really easy. Similarly, many supermarkets sell food-derived colours so if you’re the type of person to freak out over lab-produced ones you have plenty of options available to you.

Here’s how to make, bake and assemble the cake:

As a word of caution, don’t be tempted to under-bake the cakes. I’ve had a number of people ask me if that’s the way to do it, and the answer is categorically no. When you remove the cake from the oven and let it cool, the cooking process stops. You can’t make it resume by placing it back in the oven. All that will happen is you’ll have areas of uncooked batter throughout your cake, and that will jeopardise the structural integrity as well as the look and taste of your cake. Bake the cakes to completion like you would normally and don’t worry about it being dry. By covering the cake in batter and only trimming it down at the end, as shown in the video, you’ll protect the innards for the cake and it won’t dry out.

These are the recipes I used:

Layer 1: Chocolate Mudcake
95g (3 1/3oz) plain flour110g (4oz) caster sugar20g (3/4 oz) cocoa powder

1/4 tsp salt

1/2 tsp bicarbonate soda

40ml (1 1/3 fl oz) vegetable or olive oil

125ml (4 1/4 fl oz) tepid water

1 tsp apple cider vinegar

1 tsp vanilla essence

  1. Preheat oven to 180°C (160°C fan-forced/350°F). Grease or line hemisphere tin/bowl.
  2. Sift all the dry ingredients into a medium sized bowl; combine the wet ingredients in a small jug. Pour the wet ingredients into the dry and whisk until completely combined.
  3. Pour into hemisphere moulds and bake for 25-30 minutes, pending on the size of the mould

Note: this recipe should only be used for the central layer

Layer 2: Almond Buttercake
150g (5 1/4oz) butter, room temperature1/2 tsp almond essence2/3 cup (150g/ 5 1/4oz) caster sugar

2 free range eggs, lightly beaten

1/3 cup (50g/1 3/4oz) self-raising flour

1/2 cup (75g/ 2 2/3oz) plain flour

1/2 cup (60g/2oz) almond meal

food colouring (optional)

  1. Preheat oven to 180°C (160°C fan-forced/355°F). Grease or line hemisphere tins/bowls.
  2. Cream butter and sugar together until light and fluffy, beat in the eggs one at a time, then beat in the almond essence and food colouring if using.
  3. Fold in flours and almond meal a third at a time until just combined.
  4. Transfer mixture to hemisphere tin or tray and bake

Baking times: approx 33-35 minutes for 1 cup capacity hemisphere tins. For a 1 or 2 litre bowl, drop the temperature 20°C and bake for 1 1/4 to 1.5 hours.

Layer 3: Vanilla Madiera Sponge
160g (5 2/3oz) butter, room temperature160g (5 2/3oz) caster sugar2.5 – 3 free range eggs

80g (2 3/4oz) plain flour

160g (5 2/3oz) self-raising flour

Note: this is enough for a 1 litre pudding bowl. Double the quantity for a 2 litre bowl. If baking two halves for a sphere, use the 2.5 eggs. If only baking one, round it up to 3 eggs.

  1. Preheat oven to 160°C (140°C/325°F). Grease or line hemisphere moulds.
  2. Cream butter and sugar together until light and fluffy, beat in the eggs one at a time, then beat in the almond essence and food colouring if using.
  3. Fold in flours and almond meal a third at a time until just combined.
  4. Transfer mixture to hemisphere tin or tray and bake.

Baking times: approx 33-35 minutes for 1 cup capacity hemisphere tins (bake at 180°C). For a 1 or 2 litre bowl, bake for 1 1/4 to 1.5 hours.

1/2 cup (125g/4oz) unsalted butter, room temperature1 tbsp (20ml) milk3 cups (375g/12oz) icing (confectioners sugar)

optional colours of flavourings

  1. Beat the butter until pale and creamy; beat in the milk and any flavourings/colourings to be used.
  2. Beat in the icing sugar a little at a time, until all combined. If mixture is too stiff for spreading consistency, beat it a little more milk.

167 thoughts on “Spherical Concentric Layer Cake Tutorial

      • I am someone who makes cakes, but they always look… rustic… my son and I (he’s 9) are going to try this for his science project on Jupiter as an alternative to the paper mache or styrofoam ball options. Since I will never use an air brush again, I am not buying one, but have been experimenting with different colour sugars on fondant, or painting on fondant as the top layers. Any thoughts/ advice? At least mine will look like a 9 year old made it (with or without my help)!
        Thank-you so much for your detailed descriptions, you make it look very easy, I know I am delusional at this point, but we will enjoy the trial runs! Due date the 28th

  1. (NB : hey, I’m still on 31st of July here ^^ )
    This is amazing. Please tell me : do you stightly undercook the black and white cakes to avoid they go too dry or are they protected enough into the other batter?
    Thanks again for the incredible inspiration you give me 🙂

        • I agree – HOW RUDE. It must be nice to be so perfect you can be arrogant. You need to be grateful that so many appreciate your talent. And by the way your use of the F word in the previous page is totally unnecessary – that in itself is a lack of language skills.

          • I’m not entirely sure who you are agreeing with as the above comment wasn’t directed at me – you’re the first to call me rude or arrogant or ungrateful. Not sure what I’ve said to cause said impression, as I by no means consider myself perfect, nor talented.

            As for the profanity, I was merely quoting the name of the Facebook page called ‘I Fucking Love Science’. I have no qualms with quoting the name in full. I see no point creating words in a language and then demanding no one use them.

      • Thanks fot the precision, but not for your general answer anyway. Should I be sorry and crying to your knees not to be as natural as you for reading English, which is not my first language? I’m not.

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      • I am actually in the process of purchasing the needed supplies. I know for sure that the second layer. is a Silikomart Siliconflex Half-Sphere Mold, 4 Oz, 3.15″ Diam. x 1.57″ Deep, 5 Cavities. it is not cheap either! $30…however I have found some similar at a more reasonable price ( on Amazon). I am actually going to buy the Wilton mini ball pan.
        The smaller center ball is a cake pop pan. again on amazon, they range in price.

  5. I also noticed that you put flavoring in the third layer, but your recipe didn’t mention how much (vanilla I imagine ??) Could I use a vanilla pod instead?

    • You definitely could. I left the flavouring completely open here as it will depend on what someone wants to do with the layer: you can add anything from orange essence to cocoa powder. I’d go no less than half a teaspoon, but it does depend on the desired outcome.

  6. Thank you so much for sharing a tutorial for this cake. My boyfriend’s sister posted the link to your Earth cake and I thought “That’s awesome, I’ll never know how to make a cake like this.” Most bakers will post the most awesome cake pictures but keep their secrets to themselves. Thanks again for sharing!

    • You can use a butter substitute, but for this method you need a firm batter. If the cake floats or sinks in the batter then you won’t have control over the position.

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  9. This is absolutely brilliant! I, too, found you after seeing your Jupiter cake on the “I F-ing Love Science” facebook mentioned above 🙂 For my day job I manage a summer camp and after school program for girls where we do hands-on experiential activities around a variety of topics including science…for example, we learn about volcanoes by building models and exploding them…these cakes of yours have the potential to take our learnings to a whole new level! Thank you for the inspiration, the recipes and tips! You have a new reader 🙂

    • I haven’t I’m sorry to say. I’m still very much learning and (as much as this is going to sound strange given the reception is has received) I really didn’t know what I was doing. I created the cake solely to make the layer tutorial and only documented that process. I didn’t even so much as take photos of the painting progression. The exterior was just a chance for me to practise the skill and wasn’t intended as the main part of the cake. The techniques I was using at the top were quite different by the time I reached the bottom.

      I’ll probably do some fondant painting tute once I feel I have a handle on it myself. I’m throwing around thoughts of getting a kickstarter organised and maybe doing a book on making the entire solar system inside and out but I really don’t know yet. I definitely want to be more practised in it before trying to tell other people how to do it.

  10. I would definately be super happy if you could tell us more about the marshmellow icing. I tried the cake (or one of the many varieties one can make using your guidelines) and it was very good! However I failed on the icing eventhough I spent quite some time in the web researching what to do…
    Next time I was thinking about using a marzipan based icing as it seems to be easy to cut out shapes… do you think this would work?
    Anyway, the cake was a hit in our geosciences department and there are now even plans to do the whole solarsystem (in scale) based on your recipe!

  11. We love this cake and tutorial! I’m an Associate Editor of Cake Central Magazine, and we would love to feature this on CakeCentral.com! Please e-mail me if you’re interested.

    • Hey Alyssa! What a surprise “seeing” you here! Ah, I know this is out of place but I wonder, since I can’t seem to get any response from H & J about my refund for the defunct print version of CC magazine, how much longer it’s going to take for the refund I was told to request? It’s been a year waiting now & I thought maybe you’d have an update on the refunds being the associated editor and all.
      Thanks Alyssa!

  12. Pingback: Earth and Jupiter Cakes by Cakecrumbs

  13. As Jojomio can U tell me more how 2 decorate the cake ? I have no word 2 tell U how yhis cake is amazing !! Take care and thank U 4 your ideas !!

  14. Also, is the third recipe for both halves of the sphere (so, split into two batches of batter) or is that for each hemisphere? A moon cake is HAPPENING this weekend!! I too would like to know how you put the fondant on – I found what looks to be a great marshmallow fondant recipe, but I’ve never worked with fondant before and am not sure how to cover something spherical! And you would keep this cake unfefridgerated? Some say the fridge will make the fondant moist..

    • The third recipe is for the one half. I only bake one half at a time because I have the one bowl, so that’s the mindset the recipe is written in.

      As for fondant, I’ve never written a cake covering tutorial simply because there are just so many out there. If you’ve never worked with fondant before I can tell you you are likely going to find covering a sphere hard. A lot of people struggle coving a normal cake the first time. If you use the tags or the search function I have two tutorials on making fondant and, in the more recent one especially, there’s a few tips on working with it but it’s by no means comprehensive.

      As for the fridge, never put cakes in the fridge. If it had components that need to be in the fridge then there’s no choice, but otherwise never do it. Fridges completely ruin the texture of cakes, and it will mess with fondant even more so. Fondant does go very soggy in the fridge, and when you remove the cake the fondant will begin to bead and sweat. It’s a massive no-no.

      Best of luck!

      • Thanks so much for your great replies! I’m going to give this a go this weekend just in time for the perseids meteor shower.. 🙂 I had one last final question I swear.. 😛 If I dont’ use food coloring, will there still be a color distinction between the second and third layer? It seems as if the third layer might be slightly more pale?

        • There may be slightly (it will probably depends mostly on how much you cream the butter and sugar). I’d probably add something just in case (be it something like cocoa or some other flavouring) cause if the layers aren’t distinct it’s a bit of a wasted effort.

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  16. Oh boy.. it was a bit of a disaster for me !! And epic epic props to you for pulling this cake off, I unfortunately wasn’t able to! I want to share my mistakes.. First of all, I got a steel bowl that is about 6.25 inches across for the largest hemisphere. I used a nordic cake pop pan for the mud cake and a silicone mold that is a bit smaller than yours for the middle. I used a kitchen aid, and the butter(s) I used were Straus european which has 85% butterfat and is a pastured organic butter, and then i used organic valley normal butter. Eggs were organic valley eggs. I took organic sugar and pulverized it in a vitamix to turn it into caster sugar. I added some cocoa (just enough to tint, not affect flavor) to the middle layer, and the cake has a nice dark brown to medium to yellowish cake look color to it. The not so great part: My first final hemisphere (at 355 f) was very raw in the middle (I checked it for doneness at an hour – yes, too soon). When I stuck the skewer in it didn’t stick so I thought it was done, but what I didn’t realize was the batter adjacent to the core was really not done. After I turned it over the core sunk in and I ended up dissecting it to see what happened. So, to test doneness in the second hemisphere I purposely poked the skewer in right by the second core to third core zone, not just out in the third layer. The second and third hemispheres came out fine in terms of doneness, though they were very hard and crusty at the tops, and unfortunately neither seemed to puff up enough for me to be able to carve off the extra (the first just barely!). The first hemisphere had an 85% butterfat butter, the second was a normal organic stick (s) of butter, and the second one definitely didn’t seem to rise as much. I actually threw out one set of creamed butter/sugar/eggs because it started to break down and look really watery after I added the vanilla – I didn’t remember my first two hemisphere batters looking like that, they had been quite smooth and creamy. I thought I over beat the eggs, however, the second batch I made got like that also. It was also midnight and maybe my brain was just too fried for any more kitchen shenanigans.. any thoughts? It seems the quality of butter seems to make a difference (for me). I made my own self-raising flour (1 cup flour, 1.5 tsp baking powder, .5 tsp salt), and caster sugar (using a vitamix blender for the latter – if it was too fine or too coarse does this affect the cake rising ?? My egg quality was a little sketch too – I got organic nice eggs but one carton definitely wasn’t as fresh as the other, and were a little less orange and not as perky. Neither carton was as great as really fresh eggs (my chickens are not laying right now). So back to the steel bowl – the outside layer of the cake seemed almost overdone, it wasn’t as moist as the second core layer that I baked in the silicone – I wonder if the steel bowl had to do with it. I didn’t want to turn it out too soon and let it cool in the bowl – it stayed hot for quite a long time. Ok, second mistake – the batter puffs up quite a lot, so I had to really dig each ball deep into each layer and guesstimate how tall it’ll puff up. My cake ball into second layer seemed to be mostly ok, but my third hemisphere: I didn’t push in the core deeply enough, and as the cake rose, the core REALLY rose up out of the middle while the rest of it stayed just below the rim of the bowl – to get it to be a hemisphere shape i had to trim it at the lowest point and thus lost a lot of the cakeball center – this might have also been one of my less than ideal cores as the first best one got scraped in the undercooked one. So end result, I will be serving a hemisphere to the b-day boy, then bringing out the second hemisphere if people want more lol. I haven’t attempted the fondant yet, I might leave that for another day.. I’m not sure how it’ll hold up to the heat in joshua tree! I also want to add that you need to measure the oil for the mudcake by ml in a measuring cup – it does not translate into weighable ounces very well, and I would’ve put in way too much oil to make that weight (I think – I was up until 2 am baking this and this is what I remembered happening, though in hindsight I might’ve been trying to weigh it out to the tepid water recommendation – either way I will have to check for this later :/). Lastly, greasing and flouring the cake pops seemed to release better than just greasing- greasing and flouring with olive oil didn’t stick too well, so i recommend using butter or something that’ll really stick to those nonstick contours- silicone mold i just greased with butter and it was fine. The final hemisphere I buttered and floured and it popped out nicely. I feel like some of my mistakes were also attributed to rushing, though I was in the kitchen from 2:30 pm until 2 am lol. I think I could have easily spent an hour longer being much more precise though. If you have any tips as to how far down to sink the last layer it’d be a huge help I think. I tried to follow the video as closely as I could ! I hope this helps somebody out there, I apologize for the length of it!

    • Also: This made about 15 cake balls (which is a good number, I had a tough time digging some out and ruined a few due to my greasing techniques). 6 middle hemispheres. It seems like a lot of extras, but something always seems to go awry so pick the best of the best! My silicone hemishere pan was really floppy so I put it on a baking sheet, but then the very bottoms weren’t rounded and got a little toastier – not a big deal though.

      • I’m so sorry to hear it didn’t go so well for you! It can take a bit of practise – as I’ve said elsewhere my Earth cake was not perfect due to not getting the baking times correct. Sphere cakes can be really tricky and I certainly had issues with them when I first started baking.

        I always find it difficult troubleshooting tales from someone else’s kitchen but where’s what I can offer (if anyone else has some insight please do jump in):

        It is indeed odd that your eggs/butter mixture went watery. Is it possible that it curdled? Where were the eggs stored? Sometimes if you add the eggs straight from the fridge it can chill the fat in the butter and it can curdle/separate. It usually isn’t dramatic if you beat them in one at a time but it can make a difference. If this step doesn’t go right you don’t form a proper emulsion (i.e., the suspension of one liquid inside another) and this can throw off the rest of the chemical reactions that happen during the baking process. That’s the only thing I can think of.

        As for the sugar, as long as it isn’t as fine as icing sugar (confectioners sugar I think is the alternate name?) it should be okay. If you’re worried about that you could use regular sugar in future. Caster sugar is advantageous because it melts quicker which affects the amount of gluten produced during baking — but this is mainly a textural issue. However, if it is too fine it will simply dissolve into the butter during the creaming stage and won’t play it’s role properly during baking.

        The overriding problem here is of course the baking time. I’m limited in what I can say about steel bowls as I’ve never owned one (I’m currently hunting for a good set actually). But they will conduct heat differently so I can assumed that over-cooking on the outside and undercooking in the middle can be an issue. To avoid this you can insulate the bowl in any number of ways: you can use a waterbath, or wrap the bowl in a silicone mat, or a teat towel (I’ve also heard of people using newspaper) that’s been soaked in water. Some places sell things like cake rings that are supposed to insulate the bowl. The waterbath method is probably the cheapest and easiest.

        I’m not sure if that answers anything or everything properly?

        • The eggs were in the fridge and I took them out to get to room temp – the first two hemispheres I thought were fine (the eggs and butter were left out overnight), but it is possible the third was still just a little cool from the fridge as I thought I was done baking and had put them away. It’s also possible I might have overprocessed the caster sugar. I used a blender to get it more fine, but it doesn’t do it consistently, so some of it might be too fine !! Also, I used pastry flour to make self-rising flour, but an organic type – I saw little brown flecks in it as you would in more whole wheaty type flours, could that have affected the rising? Maybe I should have made the self rising flour with cake flour or normal all purpose flour.. I thought pastry flour was more fine but maybe it wasn’t! That is a really great way to insulate the bowl – I have heard of that for cheesecakes, didn’t think of using it for a hemisphere cake of sorts. Do you have suggestions on how deep to submerge each layer? Maybe just push it down far deeper than you’d expect to make up for it poofing up? Thank you so much for kindly answering all my questions, and for sharing your techniques. 🙂

    • That looks wonderful!

      The madiera sponge is unlike other sponges in that it’s not so egg based. It’s more like a butter cake so it behaves the same way.as the middle layer.

  17. HI

    I was wondeirng if you could tell me the diameter of your hemisphere pans / moulds? I have been looking to buy some to try and make this cake but am not sure about the sizes. I know you said you used 1litre but most i have seen are labelled in diameter


  18. Thanks for sharing this! Question about your recipe for step 3- Madeira Vanilla Sponge cake. You wrote: Fold in flours and almond meal a third at a time until just combined.

    Is there almond meal added to this? You didn’t have it listed in the ingredients.

    I made this exact recipe, and my batter was much thinner than yours. I was hoping for a thicker, more buttercream-type consistency like in your video. Mine was like thick buttermilk. :/

    • Ahh, copy and paste error from copying over the methods. Nope, there’s no almond meal in step 3 – I’ll amend that as soon as I’m back on my desktop.

      The batter should definitely be quite thick – was your butter at room temperature? Sometimes if it’s too warm it won’t cream properly. That’s the only thing coming to mind at the moment.

      • Yep, too warm is probably my issue! My kitchen is almost 80 degrees when the oven is off. I’m working in a new kitchen, learning curve. I’m thinking that maybe I should throw the creamed butter/sugar back in the fridge to chill out before adding my flour next time. I recall that it was getting a tad goopy on me, but I thought I could still get it to work. The other layers look great to this point. Thanks for the tip!

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  20. Is the last outer layer after the butter cream fondant? Would have love to see how you did the outer layer and coloring but besides that this is a great tutorial!!!!

    • Yup, it’s marshmallow fondant. I didn’t document that part of the process as it wasn’t originally intended to be the focus (and I was kind of making it up as I went along).

  21. Thank you so much for posting this tutorial! Your cakes are fabulous, and I’m excited to try it out for my daughter’s planet/space themed birthday party. I’m keeping my fingers crossed! Thanks again for sharing!

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  25. My son has to make a earth cake with layers for a class project. I found this site and plan to use these instructions. He is wanting to make a whole sphere. How would I cut it? it has to be displayed showing all the layers!

  26. I have a question for you. If I were to omit the two inside layers ( I do not have forms for them ) Would the baking time and temperature stay the same?

    • I think so. The mistake I made the first time was reducing the baking temperature thinking it wouldn’t have to cook as long. But the batter seems to take the same length of time to cook either way. Keep an eye on it towards the last 10-15 minutes, but it should be the same.

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  29. I was just wondering, would a Pyrex bowl work? I wasn’t sure if that’s what you were using or not. I’m trying to make a deathstar cake and I don’t want to spend over 20 bucks online and have it not get here on time.

    • Yes, that’s basically what I’m using. Just make sure to get one that’s oven safe up the the right amount of degrees. I’ve seen awful stories of people with ovens full of smashed Pyrex!

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