Sponge Cakes

Sponge cakes are European-style cakes, like the French génoise (zhehn-WAHZ), and are a fundamental block in your cake-building repertoire. Unlike butter cakes and chiffon cakes, sponge cakes include little or no fat, other than what's in the egg yolks. Traditional recipes produce cakes leavened only by the air beaten into the eggs, not by baking powder or soda.

• Sponge cakes are used in layer cakes, charlottes, jelly rolls, and tiramisu (either as a sheet or piped into ladyfingers).
• Madeleines are also a version of sponge cakes.

Since fat acts as a tenderizer, plain sponge cakes can be dry and seem tough. When soaked with simple syrup and flavorings, sponge cakes are delectable.

• Warmed eggs hold more air and create more volume when they're whipped than cold eggs.
• Whipping egg whites separately from egg yolks adds even more volume to a sponge cake batter.
• Egg yolks should be beaten with sugar until they're thick and lemon-colored; when you lift up the beaters, a "ribbon" should form on the surface as the mixture drops back into the bowl.
• Adding melted butter or sifted cocoa powder decreases the batter's volume, so fold these in very carefully.

All of these variables add to the difficulty of making a good sponge cake. Experienced bakers challenge themselves by trying to get the most volume from their sponge cakes every time they make the same recipe.

All of these recipes are best made with an electric mixer--preferably a stand mixer, so your hands are free.

• Have all of your ingredients measured and sifted and ready to go in separate bowls (you'll need plenty of counter space and equipment to make a sponge).
• Use a scale for accuracy, if you have one.
• Your cake pans should be greased and lined with parchment, and your oven preheated: sponge cake batter waits for no one.

Use a stainless steel bowl set over a pan of simmering water. Sugar has an insulating effect, and helps protect the eggs from coagulating over the heat. Add a few tablespoons of the sugar from the recipe into your egg whites, and whisk it in.

• Keep whisking the eggs while you heat them, testing now and then with your fingertip until they feel warm to the touch.
• When the egg whites (or yolks--whatever you're heating) are warm, transfer them to your mixing bowl and whip until medium-stiff peaks form.

Hot milk sponge cakes use scalded milk to warm the eggs.

Stop beating the egg whites just when stiff peaks form: you don't want them to appear dry. Perfectly beaten egg whites will fold into batter without breaking apart into white flecks and islands, and the air bubbles will still expand in the oven.

Use the "one-third, two-thirds" method for folding in egg whites:

• Add one-third of the beaten egg whites into the bowl of thick batter.
• Use a balloon whisk--one of the big bulbous ones--for best results, stirring gently until the ingredients are incorporated and the batter is lightened. (A rubber spatula, plastic bowl scraper, or even your hands also work well.)
• Add the remaining egg whites to the batter, gently folding with smooth strokes through the center of the bowl, around the sides, and lifting through the center again, repeating until batter is smooth.
• Immediately divide batter into prepared pans, smoothing the surface if necessary, and transfer them to the hot oven.
• Bake as directed.