These are possibly the most pleasurable cakes to make. I made these with my friend Lauren years ago, after she had seen the recipe in a book and knew I would want to try them out. I hadn't made them since but decided to get nostalgic for her birthday and recreate the wonderous rainbow cake!
The process is sublimely simple, just split your cake batter into equal portions (4-5 small bowls) then add a generous amount of natural food colouring, I prefer Dr Oetker as they are cheap and not full of E numbers so are safe for the little ones. Then layer in teaspoon quantities into your paper cases. The best thing is that you can apply this process to most cake batters from vanilla to lemon, obviously not chocolate. It is a bit fiddly but I'm sure you will agree the results are wonderful, perfect for kids parties or the young at heart!