Go Back Email Link

hangry little miss logo

Close-up of a slice of rainbow cake on a white plate. The whole cake is in the background.
Print Recipe

Rainbow Cake

🌈 Rainbow cake with rich vanilla-flavoured layers. Six coloured cakes sandwiched together and smothered with cream cheese frosting. Happiness in slices 😁
Before you start
Assuming you don't have six matching cake pans, you'll need to allow time between batches. This is for the cakes to cool after baking before turning them out and for the tins to cool before using them again. Each layer is very thin, so they cook quickly (about 15 minutes)
Bring the butter and cream cheese to room temperature in advance, preferably overnight
Prep Time1 hour 15 minutes
Cook Time30 minutes
Total Time1 hour 45 minutes
Servings: 24 slices
Author: Hangry Miss

Equipment

  • up to 6 cake pans 23cm diameter
  • Stand-mixer

Ingredients

Cake Batter

  • butter for greasing pans
  • plain flour for dusting pans
  • 225 g butter
  • 450 g white sugar granulated or caster
  • 3 eggs
  • Tablespoon vanilla extract
  • 225 g buttermilk
  • 60 g double cream
  • 360 g plain flour
  • Tablespoon baking powder
  • ½ teaspoon salt
  • food colouring red, yellow, blue, green (note)

Frosting

  • 270 g butter
  • 350 g icing sugar
  • 800 g full-fat cream cheese
  • Tablespoon vanilla extract
  • ¼ teaspoon salt

Instructions

  • Make the cake
    Prepare Pans - generously grease the cake pans with butter and liberally dust with flour (note)
    butter
    plain flour
  • Cream Butter & Sugar - in a stand mixer bowl fitted with the blade attachment combine softened butter and sugar. Blend at medium speed for around 5 minutes until the mixture lightens in texture and colour
    225 g butter
    450 g white sugar
  • Eggs - whisk together eggs in a small bowl. Add, a little at a time, to the creamed butter and sugar until thoroughly incorporated
    3 eggs
  • Wet Ingredients - add in vanilla extract, buttermilk and cream
    Tablespoon vanilla extract
    225 g buttermilk
    60 g double cream
  • Dry Ingredients - in a separate bowl, whisk together the flour, baking powder and salt
    360 g plain flour
    Tablespoon baking powder
    ½ teaspoon salt
  • Combine Dry with Wet - in two batches at low speed, add the dry ingredients to the wet. Combine just enough so that there is no dry flour visible
  • Divide Batter - evenly into six bowls (note)
  • Colour Portions - add food colouring to each bowl. You want red, orange (equal parts red and yellow), yellow, green, blue and violet (mostly red with a few drops of blue). Use a rubber spatula to combine well
    food colouring
  • Bake - dollop each colour batter into the centre of a cake pan and spread out evenly. Cook for 10-15 minutes, until the centre is set. You’ll get a feel from the first batch - test every minute from 10 minutes
  • Cool & Turn Out - let the cakes cool a little in the pans before turning out. They will shrink away from the pan around the edge. Use a flexible spatula to work around the edge and under, all the way around the perimeter. Shake the cake slightly within the pan until you see it shift and you know it's loose. Gently put your open palm on top of the cake and tip out close to a cooling rack. You want the cake to fall out ever so gently. Allow the cake layers to cool completely before icing
  • Repeat - steps 9 & 10 for the remaining portions of batter. Allow the pans to cool completely in-between batches. Wipe them out gently with paper towel to brush out any cake crumbs
  • Frosting
    Cream Butter and sugar - add the butter to a stand mixer bowl. Sift in the icing sugar. Blend together at low speed using the blade attachment until well blended
    270 g butter
    350 g icing sugar
  • Cream cheese, Vanilla & Salt - add these and mix at low speed until well combined
    800 g full-fat cream cheese
    Tablespoon vanilla extract
    ¼ teaspoon salt
  • Assembly
    Layer Cakes - in rainbow order with icing in-between. From bottom to top - violet, blue, green, yellow, orange & red. Use about half the icing for sandwiching layers, the other half for the outside.

Notes

It's worth spending a bit more on good food colouring - you'll need to use far less to get the same intensity of colour.
Weigh your batter and divide this by six so that you can have even cake layers. It's handy if you know the starting weight of your mixing bowl. This way you don't have to transfer to another bowl to weigh.
 
Make Ahead
You can make the icing and the cakes a day in advance and assemble on the day. Wrap the cake layers individually in plastic wrap. Keep the cake layers out of the fridge until assembled and frosted. You can refrigerate the icing but bring it to room temperature before attempting to use.