I’m a firm believer that you can never have too much colour in your life, especially now in the fall when the weather’s getting all drab (the trees get it, though, all the reds and yellows and oranges out there on their branches!). While this rainbow cake may not be perfectly in season, it is a ton of fun to make, and even more fun to look at and admire – and, of course, eat! So if you’re looking for an excuse to go a little baking crazy, follow this recipe and you’ll end up with a deliciously whimsical treat!
Here’s what you need:
For the cake –
- 1 1/2 cups self-raising flour
- 3 tsp baking powder
- 1 1/2 cups butter, softened
- 1 1/2 cups sugar
- 6 large eggs
- 1 tsp vanilla extract
- up to 40 ml of milk
- gel food colouring, 6 colours (do not use liquid, otherwise the colour will not turn out nicely; I used Concentrated Gel Icing Colours by Wilton)
- you’ll also need 6-in cake pans; not to worry if you don’t have 6 pans (I didn’t), you can bake the cake in batches (I had 3 pans, so I did two separate bakes to get my 6 layers of cake)
For the icing* –
- 1 cup butter, softened
- 2 packages of cream cheese (total 500 grams of cream cheese)
- 4 1/2 cups icing sugar (can probably reduce to 4 cups)
- 2 tsp vanilla extract
*these amounts should get you plenty of icing to go around for the cake, with some remaining
Here’s what you do:
For the cake –
- Preheat oven to 360°F; grease the bottoms and sides of your cake pans with melted butter, and set aside (you may have to do this multiple times depending on how many pans you have; just make sure any time you put batter into the pan, it’s been greased)
- Cream together butter and sugar until light and fluffy
- Next, add eggs one at a time, mixing after each addition
- Mix in a little of the flour; once fully incorporated, add the rest of the flour, the baking powder, and the vanilla extract; mix well
- Depending on how thick your mixture is, you may add up to 40 ml of milk to it, doing a tablespoon at a time; I added only one tablespoon to my mixture
- Next comes the fun part – colouring! Divide your mixture into 6 different bowls/containers; I measured mine out so that I had approximately 185-200 grams of batter in each container
- Once the batter is evenly divided into 6 sections, add one colour to each container and mix it up until well incorparated. You won’t need much; start by adding a little, and then go from there until you’re satisfied with the shade
- Bake for 8-10 minutes, taking the cakes out of the oven as soon as a toothpick inserted comes out clean; be sure to check on your cakes frequently to make sure they’re not turning brown – you may want to rearrange where they sit in the oven as they bake, although I did not find this was necessary
- You may need to bake your cakes in stages, like me; I only had three pans so I did three colours at a time; therefore, be aware that if you’re putting in a different amount of cakes than me, your baking times may vary, so be sure to keep an eye on your cakes! I would say, check all your cakes at 8 minutes, then if they’re not ready, continue to check on them at 2 minute increments


- Once baked, allow cakes to cool; ensure that they are completely cool before you begin icing**
**I suggest making your cakes (and your icing) the day before you plan on icing your cake. Plan for this cake to take you at least two days. Day 1 will be baking the cakes and making the icing. Day 2 will be assembly, icing, any extra decoration, and serving. On Day 1, once your cakes have cooled, take them out of their pans and carefully wrap each individual layer in plastic wrap. Then, place your cakes in the freezer for at least several hours (mine were in there for about 6 hours); this will help with icing the next day. Overnight, remove you cakes from the freezer and place them in the fridge, to semi-defrost but to still keep cool. You don’t want to ice solid blocks, but you want your cakes to be firm when icing, which is why you should make the move to the fridge for keeping over night. The icing, too, once made, should go into the fridge for the night.
For the icing –
- Add the butter, cream cheese, icing sugar, and vanilla extract into a Cuisinart, or stand mixer, or large bowl with electric mixer, and mix everything together until well incorporated
Assembly time! –
- If you made your cakes and icing the day before, take everything out of the fridge, along with the platter or cake stand you wish to use to present your cake
- Smear a little icing in the middle of the platter/cake stand, to help hold your cake in place while you work on it
- Put down your first colour in the center of the plate. I started with purple and made my way up to red, but feel free to place your colours in whatever order you please
- Do a thin layer of icing on top of your first colour, out to the edges (ensure that it is thin, so that it doesn’t squish out the sides the more weight you add to the cake)
- Place your next colour on top, lining it up with the first; continue like this until all layers of cake have been added – cake, icing, cake, icing, cake, etc.

- Once your cake has been fully assembled, you’ll move on to what is called the crumb layer – the first layer over the entire cake that will encase all the crumbs so you don’t have to worry about them later. Use this layer also to fill in any gaps that might appear between your cakes. This first layer doesn’t need to look nice, and don’t worry about the colours showing through this layer, because it’s all going to be covered up. Once you’ve finished the crumb layer, place your cake into the fridge and chill for an hour

- Apply a second layer of icing; chill for an hour***
- Apply a third and final layer of icing, chill until serving/decorating time, at least one hour
***Feel free to stop after the second layer, depends on how much you like icing/how much icing you made

You can then add rainbow sprinkles to decorate, or whatever your heart desires! I suggest doing the final decorations just before serving. (I got so excited about serving my cake and seeing the inside, that I forgot to add the sprinkles.)
Enjoy and prepare to be amazed as you cut into this fantabulous rainbow-coloured cake!
It looks good! I sure will try this recipe! I have never seen anything like this.👌
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Thanks! I’m by no means a professional baker, so I was really impressed by how easy it was to make it look that beautiful. It was a lot of fun too!
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Your cake turned out beautiful! I did this with cupcakes (it was a much smaller scale) one Easter and the kids loved them–but they did not turn out as beautiful as your cake.
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Thank you! Cupcakes would be hard, they’re so small! How many layers did you do on the cupcakes?
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I only did four colors and kept them pastels–they were pretty, but not like your cake!
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My next colour project, I definitely want to do pastels. They’re my favourite!
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