I had seen these rainbow cakes on pinterest and thought they looked like a great idea for a Children's birthday party as all the children would be really surprised to see the rainbow colours when you cut the cake. However my children's birthdays aren't until the summer so instead I though I would make one for my 68 years young dad as it was his birthday in December!
Basically the idea is that you make up different coloured layers of cake so that they form a rainbow effect inside the birthday cake. You can use a method where you make and cook a different coloured layer at a time holding them together with a layer of icing but, because I didn't have much time, and I'm a little bit lazy I thought I would try just layering the colours on top of each other in the same cake tin. This seemed to work fine although it gave a bit more of a swirl effect than if I had done them separately. I had also read online that you needed to use gel food colouring to get a more intense colour but as I couldn't get hold of these in any local shops I experimented with using normal food colouring and found that you still got a good colour. So here is my rainbow cake recipe.
Ingredients (makes 1 round cake)
300g self raising flour
300g caster sugar
a couple of drops of vanilla essence
red, blue, yellow and green food colouring.
Firstly make up the cake mix by mixing together all of the ingredients.
Then divide into four bowls and add a different colour to each bowl. Use a bit of food colouring at a time until you get to the desired colour.
Put the mixtures into the cake tin in layers of each colour and cook in an oven at around 180c for 50 mins-l hour
Take the cake out and ice and decorate as required. The outside will brown in the oven but when you cut into it you will see the rainbow colours appear.