Génoise

Preparation

1. Step 1

   Coat a 12 × 16-inch rimmed baking sheet or a 9-inch round cake pan with cooking spray. Line with parchment; coat with cooking spray. Dust with flour, tapping out excess. Stir together the flour and salt into a medium bowl; set aside. Preheat the oven to 450°F for a sheet cake or 400°F for a round cake, with a rack in the lower third.

   Step 2

   Put the eggs, egg yolks, and granulated sugar in the heatproof bowl of an electric mixer. Set over a pan of simmering water; whisk until the sugar has dissolved and the mixture is warm to the touch. Return the bowl to the mixer, fitted with the whisk attachment. Beat on medium-high speed for 2 minutes. Raise speed to high. Beat until the mixture is pale and thick, about 4 minutes more.

   Step 3

   Remove the bowl from the mixer. Sift the flour mixture over the top; using a large rubber spatula, carefully fold it into the egg mixture, cutting through the middle and lifting gently over the sides. When almost incorporated, pour the melted butter down the side of the bowl; gently fold to incorporate completely.

   Step 4

   Spread the batter evenly in the sheet or pan with a large offset spatula. Bake until golden brown and springy to the touch, about 6 minutes for a 12 × 16-inch cake and 15 minutes for a 9-inch round cake.

   Step 5

   For the 12×16-inch cake: Run a small knife around the sides of the baking sheet; invert cake onto a wire rack. Remove the parchment. Reinvert the cake onto the rack. Let cool completely.

   Step 6

   For the 9-inch round cake: Let cool in the pan on a wire rack for 15 minutes; run a small knife around the sides of the pan. Invert onto a rack; remove the parchment, and reinvert onto the rack. Let cool completely.