A true sponge is leavened only by eggs, not baking powder. This is a true sponge cake that is perfect for your Victoria sandwich and lots more.
Instead of baking the cake in two sandwich tins, you can bake it in one swiss roll tin to make a swissroll. When done just remove from pan onto an icing sugar-dusted tea towel, trim the edges and roll using the tea towel. When cool unroll and add your favourite filling.