• 1 to 2 tablespoons butter, softened, for the pan
• 6 large eggs, separated
• 6 tablespoons sugar
• 6 rounded tablespoons cake flour
• ½ teaspoon baking powder
• ¼ teaspoon salt
• 1 teaspoon pure vanilla extract
• 1 to 2 tablespoons powdered sugar

Preheat the oven to 375°F. Butter a 15-by-10-by-1-inch jelly-roll pan and line it with baking parchment. Butter the parchment.

With an electric mixer, beat the egg whites at medium speed until soft peaks form. Gradually add the sugar while increasing the speed to high. Beat until the whites stand in stiff peaks when you lift up the beater. In a separate bowl, beat the egg yolks until fluffy and pale yellow in color. In another bowl, sift together the cake flour, baking powder, and salt. With a rubber spatula, gently fold the egg yolks into the whites, then gradually fold in the flour and vanilla.

Pour the batter into the prepared jelly-roll pan and spread it evenly out to the edges of the pan. Bake on the middle rack of the oven until the top is golden and a toothpick inserted in the center comes out clean, about 15 minutes. Use a sharp knife to trim off the crisp edges of the cake. While the cake is still warm, invert it onto a clean, slightly damp kitchen towel that has been dusted with powdered sugar. Carefully peel off and discard the parchment. Roll up the cake in the towel, starting from the shorter side and rolling away from you. Set aside to cool for 5 minutes before filling the cake according to one of the recipes that follow.