A cake made from a mixture of egg yolks and sugar, which has been beaten until fluffy, and then has beaten egg whites folded into it. The eggs are the only leavening agent in the cake. The cake has a delicate, airy texture. Sponge cakes do not contain any shortening and can be made in various flavors, such as vanilla, lemon, orange, chocolate, raspberry, blueberry, pineapple and almond.