Sponge Cake
6 eggs 1 cup granulated sugar rind of half a lemon 2 tablespoons lemon juice 1 cup flour 1 teaspoon Royal Baking Powder 1/2 teaspoon salt Beat egg yolks with wire whip until thick; add gradually sugar which has been sifted, then grated lemon rind, lemon juice and one-half beaten whites; mix well; carefully cut and fold in flour which has been sifted with baking powder and salt; add remainder of whites. Bake in ungreased sponge cake tin in moderate oven 35 to 45 minutes. When cake shrinks from pan remove from oven and turn upside down on cake cooler. It will gradually come out of pan.
A classic foam cake that leans on beaten eggs rather than fat, with a small insurance policy of baking powder. The method is sound as written; a few of the terms need translating.
- Oven temperature"moderate oven" in books of this period is usually read as about 350F, though the range given in contemporary sources runs to roughly 375F. The recipe's own 35 to 45 minutes is the guide; a shallower pan may well be done sooner.
- The sponge cake tinAn ungreased tube pan, roughly 9 to 10 inches, with a removable bottom if possible. The batter must be able to grip the sides as it climbs, which is why nothing is greased and why a nonstick pan is the wrong choice.
- Baking powder in a spongeThe recipe names Royal Baking Powder outright, which points to a Royal promotional cookbook, hence the teaspoon in a cake that traditionally uses none. It works, but the eggs are still doing most of the lifting; beat the yolks until they are pale and hold a ribbon, and take the whites to soft, glossy peaks rather than dry ones.
- Adding the whites in two stagesHalf the whites go in first to loosen a dense yolk-and-sugar base, the flour is folded into that slacker mixture, and the rest of the whites go in last so the final structure stays aerated. Folding the flour into a stiffer mixture tends to cost you volume.
- Folding"Cut and fold" means a spatula down through the centre, along the bottom, and up the side, turning the bowl as you go. Sift the flour over the surface in two or three additions rather than dumping it in.
- FlourA cup of soft-wheat or cake flour gives the tenderest result; all-purpose works but weigh it at about 120 g and do not pack the cup.
- Cooling upside downInverting is not optional. The hot crumb is fragile and will collapse under its own weight if left upright. If the pan has no feet, hang the tube over a bottle neck until the cake is completely cold, then loosen the edges with a thin knife.
- YieldOne tube cake, roughly 10 to 12 servings. Being fat-free it is leaner than a butter cake, and such sponges were commonly served with fruit, cream or a lemon glaze.
Sponge cake predates chemical leavening entirely; recipes for cakes raised on beaten eggs alone appear in English cookery books from the seventeenth century onward, and the technique spread wherever cooks had eggs, sugar and patience with a whisk. This version reads like something from a baking powder company's promotional cookbook, and the single teaspoon of Royal in an otherwise traditional formula suggests what such a book was for: these volumes were given away or sold cheaply through the early twentieth century to persuade home bakers that the manufacturer's product belonged in every recipe, including ones that had managed without it for centuries. The lemon is the older element here, and is often said to have been the standard flavouring for a plain sponge long before vanilla extract became a household staple.