Keeping Air in the Egg Whites

Maintaining the air bubbles in the whipped egg whites is essential for a light texture in the sponge cake. When folding in the egg whites, do not stir to combine with the other ingredients, but rather use a whisk and a careful fold, lift, and turn motion to incorporate all ingredients. Once the egg whites are incorporated and the batter is ready, proceed with care when pouring it into the baking pan so the batter settles evenly. When all the batter has been poured, gently tilt the pan to distribute any uneven batter and then smooth the top with a light touch. These details are small but important with sponge cakes. If the batter is poured roughly, it loses air in the egg whites, and if the top of the batter is not smoothed, the cake will bake with a mound in the middle, which is a problem, especially with round sponge cakes. The mound shape, unless cut off, makes it difficult to smooth fillings, toppings, and decorations onto round cakes.