GENERAL CLASSES OF CAKES
21. Although many varieties of cake can be made, they may all be put into two general classes: sponge cake and butter cake. These classes may also be regarded as cake made without butter and cake made with butter, for it is the presence or absence of fat in a cake mixture that makes the difference in the method of mixing the ingredients and determines the texture after baking. While there are many true examples of each of these classes, it must be remembered that there are also numerous variations of the two which must be placed in either one or the other of these classes. For instance, a true sponge cake does not contain baking powder, but some recipes for sponge cake are given in which baking powder is included. Such recipes must be regarded as variations of sponge cake, for they are more similar to that than to butter cake.
The ingredients are not, however, the only source of difference between these two general classes of cakes. They also differ as to the method used to combine the ingredients, the correct oven temperature for baking, and the length of time required for the baking. All these differences must be thoroughly understood if successful cake making is to be the result.