Is rainbow cake on your list of bakes to try? This rainbow cake recipe is easy to follow and is great for any special occasion. It’s an impressive cake recipe which is guaranteed to get you a lot of compliments. What birthday girl or boy wouldn’t be delighted with this brightly coloured rainbow cake? Imagine their surprise when they cut into it! It’s not difficult to make with our easy mix sponge cake recipe, you just have to be bold with the colours and use concentrated gel paste colours which are now widely available in major supermarkets, cake decorating shops and online. Use 18cm round sandwich cake tins, you’ll probably need to bake the sponges in batches, if you don’t have 5 tins, but this is not a problem as the cakes don’t take long to cook. Once baked you can freeze the sponges until you are ready to assemble and decorate.
- 500g sunflower spread (not low-fat), at room temperature
- 500g caster sugar
- 500g self-raising flour
- 10 eggs, at room temperature
- Gel paste food colours in colours of your choice
- For the buttercream icing:
- 400g icing sugar
- 200g butter, softened
- Food colouring, as desired
- Coloured sprinkles, to decorate
Preheat the oven to 180°C/350°F/Gas Mark 4. Grease and line the base of 2 or more 18cm diameter sandwich cake tins. You’ll need to bake 5 cakes in total but the tins can be reused.
Place the sunflower spread, caster sugar, flour and eggs in a large mixing bowl and whisk together using an electric mixer until soft, smooth and creamy.
Divide the mixture equally between 5 bowls. Add a small amount of food colour to each bowl, mix to colour evenly, adding more colouring if necessary to get vibrantly coloured mixtures. Spoon a coloured mixture into each tin and spread level with the back of a spoon. Bake for 30-35 mins until well risen and just firm to the touch. Cool in the tin for 5 mins then turn out onto a wire rack to cool. If reusing the tins, wash, grease and line with clean paper before adding the next mixture.
For the buttercream, beat the butter with an electric mixer until smooth. Add the icing sugar, about one-third at a time, whisking well between each addition until smooth. You need a soft spreading consistency so if the buttercream is too stiff add 1tbsp freshly boiled water from the kettle and whisk again until light and fluffy. If you’d like to use colours, add a few drops of each to separate bowls of buttercream and blend until evenly coloured.
To assemble, place the pink cake on a plate or board and spread with a thin layer of buttercream. Build the cakes in a rainbow order of colours, spreading a thin layer of buttercream between each one. Using a round bladed knife spread the remaining buttercream over the top and sides of the cake, swirling it slightly. Decorate with coloured sprinkles over the top.
This cake will keep for 3-4 days in an airtight container stored in a cool place.