I made this (yummy) sponge cake last week with the simplest of methods.
100g caster sugar
100g self raising flour
Mix together and bake for 20 mins or until spongy.
I also made butter icing for the topping, mmmmmmmmmmmmmmmmm!
115g icing sugar
A splash of milk
A drop of Vanilla essence
It's the best sponge, even if I do say so myself.