(this is enough for 7 x 6-7 inch cakes)
420g self-raising flour
7 different food colourings (Wilton is the best)
350g unsalted butter, softened
700g icing sugar
4-5 tbs milk
Preheat the oven to 170C.
Combine all the ingredients, being careful not to over mix.
Separate the mixture into 7 bowls each containing equal portions (you can weigh them if you find it easier).
Add a drop of food colouring (to each batter portion) and mix until it is all combined. Feel free to add more food colouring until you reach your desired colour.
Add 1 capful of vanilla essence to each batter portion.
Pour the batters into 7 separate 6-7 inch lined and greased cake tins.
Cook each cake for 25-30 minutes or until your knife comes out clean.
To make the icing: add butter into a mixing bowl and using an electric whisk, slowly add the icing sugar until it is all combined. Add as much or as little milk as you like (as depends on what texture icing you are looking for) we think 4tbsp is perfect!
Remove your cakes from the oven when cooked, turn out onto a cooling rack and leave to cool.
When fully cooled, begin layering your multi-coloured cakes, spreading icing evenly between each sponge.
Cover the multi-coloured sponges in icing and decorate however you wish!