Equal parts by weight (tradtionaly one pound of each):
- Cream butter and sugar.
- Add eggs and beat.
- Fold in flour.
- Pour in greased loaf or bunt pan.
- Bake ...
Substitutions and Variations
Traditional English sponge cake is equal parts eggs (typically three), fat, sugar, and flour. So a variety of fats may be used.
Substituting oil for some of the butter is intended to produce a moister cake. Sour cream and mashed bananas have been added for the same reason.
An early American variation was to replace part of the flour with cornmeal. This was popular in Ireland as a cost cutting measure.
Citrus juice (commonly lemon) is a popular addition, often with poppy seeds. Vanilla, rum, fruit, and/or nuts are also common.
The standard recipe is quite dense, so modifications intended to produce a lighter sponge are common. The most popular, Victoria Sponge, adds baking powder. Those that add an acid (such as lemon juice) can use baking soda for the same effect. A French method is to beat the egg whites separately and gently fold them into the batter.