Sponge Cake

6 large eggs, separated, at room temperature

1 cup (198g) superfine sugar (or regular sugar ground in food processor for 1-2 minutes)

2 teaspoons vanilla extract

1/4 teaspoon salt

1 cup (120g) unbleached cake flour (or put 2 tablespoons cornstarch in measuring cup and fill remainder with all-purpose flour)

Heat the oven to 350°F.  Grease your choice of two 8" (at least 2" deep) or 9" round pans, or one 9 x 13” rectangular pan.  Line the bottoms with parchment paper, then butter and flour the paper.

Combine the egg yolks and 3/4 cup of the sugar in a large bowl.  Using an electric mixer, beat on medium-high speed until the mixture becomes pale and thick, 3 to 5 minutes.  Stir in the vanilla and salt.

In a clean bowl with a clean whisk attachment, beat the egg whites until soft peaks form.  Gradually add the remaining 1/4 cup sugar, beating on medium-high speed until the whites are stiff and glossy, about 2 minutes.  Fold the yolk mixture, one third at a time, into the whites.  Sift the flour over the mixture and fold gently until incorporated.

Divide the batter evenly between the pans.  Bake for 20 to 25 minutes, until the edges just begin to pull away from the pan and the center springs back when lightly touched.

Remove the cakes from the oven and let cool in the pans on a rack for 5 minutes.   After 5 minutes, turn the layers out of the pans, peel off the paper, and return to the rack to finish cooling right side up.

From King Arthur Flour