How to make a rainbow cake

Just when you think there can’t possibly be another baking phenomenon, unicorns take over the world and the rainbow cake is born. Keen to try this multi-coloured, crumb-coated wizardry at home? Here’s how to make a rainbow cake.

Rainbow-cake-first

Ingredients:

You will need to make this sponge recipe twice (so you will need to double the sponge ingredients below) to make six layers.

For the sponge

225g butter, softened
225g castor sugar
1 tsp (5ml) vanilla extract
4 jumbo eggs, at room temperature
225g self-raising flour, sifted
Food colouring – red, orange, yellow, green, blue and purple. We used the Wilton Gel Food Colouring.

For the icing

100g butter, softened
1 tsp vanilla extract
½ cup (125ml) icing sugar, sifted (plus a little more just incase)
4 x 250g cream cheese

Method:

1. Preheat the oven to 180°C.
2. Lightly grease 3 x 20cm PushPan cake tins and set aside. Cream the softened butter and sugar together using an electric beater or stand mixer until pale and cream in colour.
3. Add vanilla extract and eggs, one at a time, making sure you beat in each one before you add the next. Fold in the sifted flour and then divide the mixture into three mixing bowls making sure that the weight of all three mixtures is equal.
4. Pick three of the colours (remember you’re going to be making the recipe twice to get all six colours) and add a little into each batter bowl, adding more until you are happy with the colour. Be careful not too add too much colour in the beginning, as you can always add more food colouring to achieve a brighter coloured cake.
5. Pour each batter into the three prepared baking tins and place into the oven for about 15–20 minutes or until the cake is cooked and a skewer inserted into the centre of the cake comes out clean.
6. Remove cakes from the oven and allow to cool for a couple of minutes in the cake tin before gently pushing out and carefully placing on a cooling rack to cool completely. If the cakes rose with quite a peak in the centre you may want to trim this level with a bread knife. Don’t be disheartened by the dulled outside colour of the cake. The baked food colouring will look odd but the inside of your cake with be delightfully bright still, rest assured. Repeat this recipe using the remaining three food colour gels to achieve your six layer rainbow cake.
7. To make the icing, place the softened butter and vanilla extract into a large mixing bowl and, using an electric beater, cream until smooth.
8. Add in the sifted icing sugar and beat until well incorporated. Add cream cheese and whisk until smooth.
9. Taste the cream cheese icing and add more icing sugar if you would prefer a sweeter icing.

How to assemble a rainbow cake:

1. Smear a little icing onto a cake stand and place the purple coloured sponge onto the blob of icing. This prevents the cake from sliding around the platter. You may want to place your cake layers top side down, so that the flat ‘bottom’ faces upwards, this also ensures that your layers are even and less tapered.
2. Then spread a generous amount of icing onto the purple sponge, making sure you spread the icing right to the edge. Place the blue sponge on top of the iced purple sponge and repeat this icing process following with green, yellow, orange and finally red. Again, don’t fret if your cakes aren’t as bright as you expect them to be – the true colour won’t show on the outside.

rainbow-cake-layers

3. Spread a thin layer of icing all over the cake to secure any loose crumbs on the surface of the cake.

Rainbow-cake-icing

4. Refrigerate the cake for ten minutes to allow the crumb coat to set. With the crumbs now secured, very generously smear the remaining icing all over the sides and top of the cake. Sprinkle with hundreds and thousands if you want a truly colourful cake or leave plain with the brightly coloured surprise on the inside.

rainbow-cake-slices

There may not be a pot of gold at the end of every rainbow but there sure are a bunch of happy (and full) people at the end of a rainbow cake.

How do you remember the colours of the rainbow?

Thanks to Luisa Farelo for her recipe and styling.

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Written by Andrèa Fedder

From yoga to painting, baking to recycling, Andrèa is our editor and she is interested in everything. When she's not skilfully honing or writing articles and drawing on chalkboards, she can be found, salt in her hair, sand in her toes, on a beach with her golden retrievers. View more articles by .

35 Comments

  1. Vickie says:

    One of my science teachers taught us to remember it with the mnemonic ROY G BIV (Red, Orange, Yellow, Green, Blue, Indigo, Violet) :-)

  2. Naz says:

    Thank you so much for posting this!!!
    I’ll be making this cake for my daughter’s daycare class party – she’s in the “Rainbow Class”
    And to think, I was going to get cake mix off the shelf
    Love-love-love u guys …

  3. Rozanne says:

    Thank you so much Yuppie Chef. I’m planning to make this for my baby’s first birthday next month!

  4. dilshaad says:

    my son’s 1st birthday is coming up, and with him being at school while i’m at work, i REALLY want to make a cake myself. although i won’t be this adventurous yet with 6 colours, will “steal” this recipe and try a 2-tone cake. as always, the Yuppiechef team is awesome!

    • Yuppiechef says:

      Hi Dilshaad,

      That sounds lovely and we’re sure your ombre cake will be equally as magical. :) We’d love a pic if you felt like sending one. Happy baking.

  5. Thevi says:

    Thanks for this! Can’t wait to try it….
    Your Biggest Fan :)

  6. Brenda says:

    This cake looks beautiful. I have a question not related to this recipe but I’ve seen it used in numerous recipes. Golden Castor Sugar. Is it available in supermarkets in South Africa? Can’t say I’ve seen it.

    Have spent the past few days on Yuppiechef. Love it.

  7. Pho says:

    Many thanks, for the recipe am surely going to try it out for my Grandson who is patiently awaiting my arrival.

    Also please give recipe for soft delicious biscuits.

    I love coconut, but am not sure how to adjust my measurements, please help.

  8. Shriya says:

    Wow. This is just wonderful. Ty so much. I’ve tried it and it has come out just spellbinding <3

  9. dilshaad says:

    Ps. i DID in fact use this recipe for my son’s birthday cake. the initial green and blue batches came out so lovely i ended making a 3rd red layer. also, i chose to go very dark (more than half the food colouring bottle) – the mixture might look odd raw, but once done it was so rich in colour i had to change the decor plan and not ice the sides to show off the cake a bit more. DEFINITELY a recipe worth saving! (unlike many ‘internet’ recipes)

  10. foodie says:

    Im turning 15, im going to bake this and use reg. Frosting. Super Excited

  11. Gisela says:

    Hi guys!

    Dying to try this recipe for my boy, Karl’s third birthday party this weekend.

    It is a space party, any idea how I can make a rocket cake and incorporating this?
    He actually asked for a rocket cake so don’t want to disappoint him….

    Thanks and love you guys!

    • Yuppiechef says:

      Hi Gisela,
      This sounds like a great idea. We’d love to see how it turns out! Please send us a pic. You could use fondant icing to create the ‘rocket’ theme. We just had a quick look on Pinterest for ‘rocket cakes’ and there are lots of great ideas on there and Nicoletta ready-to-roll fondant icing works well: http://www.yuppiechef.com/nicoletta.htm?id=6774&name=Nicoletta-Ready-to-Roll-Fondant-Icing-250g.
      Keep in touch.

    • Yoli says:

      I made this for my boys 5th birthday, and we did a star wars angry birds theme – so put the fondant on the top (to save some money) and put the little space figures on the top and then used normal blue icing around the sides and put loads of smarties in it. It was an awesome cake. It tasted great and it looked beautiful.

  12. Gisela says:

    Thanks so much will send feedback!

  13. Yolandie Hayden says:

    Baked this cake for a fourth birthday party and what a response I got!
    Thank you for this easy to follow recipe that delivers such amazing results. Kids and adults loved this cake 😊

  14. mel says:

    How long can this cake be made before you need it. I have a party sunday and was wondering when to make it ? Please help :)

    • Yuppiechef says:

      Hi Mel,

      You can definitely make the cake in advance, as long as you keep it in an airtight container.

      We suggest making the icing before hand but only icing the cake the day you intend serving it. :)

      Hope it goes down a treat!

  15. Saira says:

    Hi! I am planning to use this recipe for my sons 7th birthday but have a few questions. ..
    1. For the frosting, is half a cup of icing sugar enough for sweetness?
    2. How is the thickness of this frosting? Can I pipe rosettes with it?

    Thanks!

    • Yuppiechef says:

      Hi Saira,

      Yes half a cup was plenty sweet enough – this cake was gobbled up in minutes.
      The cream cheese content would make the icing quite thick, but you could always test it with a smaller amount and if it’s too thick to pipe, add a little more melted butter. :) Good luck and happy birthday to your boy!

  16. Saira says:

    Thanks alot for your reply ! Is the measurement under frosting enough to layer, crumb coat and top the cake ? I am making it as a surprise for him :)

    • Yuppiechef says:

      Hello again.

      Yes the icing measurements included are for the layering and the final coating.

      Perhaps make sure you have extra icing ingredients at hand in case you find yourself layering the icing between the cake on the rather generous side. That way you can always whip up another batch. :)

      Hope he enjoys it – do send us a picture!

  17. Cindy says:

    I have made a rainbow cake before but i am looking forward to using this recipe. I plan on making this cake as a surprise for my niece on her 9th birthday.

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