Rainbow cake

Its someones birthday tomorrow! And I don't really know them, so cake is an obvious present-solver.
Usually I do cupcakes, but I wanted something easier to carry, and recently I've gotten more into cakes then cupcakes, and also by making a cake there was leftovers and my housemates are loving me so much.

I made this cake mixture and then divided it into 5 bowls and made them red, purple, blue, aqua-ish and orange.

Then I put one colour at the bottom of a greased tin and spread it out a little, then put another colour on and spread it, and so on until all colours were used and the batter was spread almost all the way to the edge.
Then I baked it and cut a nice square out of it.


Tomorrow I'm going to ice it and cover it in sprinkles, and probably a happy birthday message. I'll post up photos when its all done :)


BTW my icing recipe is:
About a tbsp of butter melted in a saucepan (purely because we don't have a microwave yet, if you have one use it instead of a saucepan >.<)
Then add icing sugar and tsps of hot water until you reach the right consistency and quantity.
For this one I'm going to seperate it into bowls and add colours, then put small blobs of it over the cake, then spread it around, hopefully making an awesome rainbow swirly icing. Then I'll pipe happy birthday on top once the icing is set (if you don't make a large quantity of icing and so don't have much water in it, it will be a lot greasier and not set hard. If you're just making a small amount just use a tsp of butter, unless you want it greasy and soft that is.)