Lemon Sponge Cake

Sponge cake, so called because of its airy structure reminiscent of a sponge, is a light cake perfectly served with berries (or other soft fruit) and whipped or ice cream. Unlike butter cakes, sponge contains no rising agents (such as baking powder, baking soda or yeast) and little or no butter. Whipped egg whites provide the height, which makes the cake especially susceptible to falling if the oven is opened during baking. The crumb can be described as a hybrid of pound cake and Angel Food cake.

While simple on its own, sponge cake often forms the foundation of ornate desserts such tiramisu, trifle, and Buche de Noel (Yule Log). This version incorporates lemon zest to add a citrus flavor and fresh scent.

Serves 12

Ingredients
8 eggs, separated
1 cup of granulated sugar
2/3 cup unbleached all-purpose flour
1/2 cup cornstarch
3 tablespoons unsalted butter
zest of 1 lemon
1 teaspoon of lemon extract (optional)
powdered sugar (optional)

Directions
1. Line a 10-inch springform pan with wax paper or parchment paper. There is no need to grease the pan. Preheat the oven to 350 F.
2. Whip egg whites until frothy. Slowly add sugar and beat until glossy and stiff.
3. In another bowl, using the same hand mixer whip egg yolks, lemon zest and lemon extract until creamy, approximately 2 minutes.
4. Using a rubber spatula, gently fold the egg yolks into the egg whites. Be careful not to overmix which will deflate the egg whites.
5. Combine the flour and cornstarch and gently sift into the egg mixture. Fold in carefully, then fold in melted butter.
6. Transfer the batter to the pan. Spread evenly with the spatula and shake the pan to remove air bubbles.
7. Bake for 30 minutes or until a tester inserted in the center comes out clean. Once the cake has cooled, run a knife around the cake to detach it. To serve, slice with a serrated bread knife.

To serve, dust with powdered sugar and slice with a serrated bread knife.