The recipes here mostly lean on the leavening-free definition, but you'll find all manner of sponge cake. What they all have in common is their most important quality: They're delicious.

Bake the cake until it is golden brown, it springs back to the touch, and a toothpick inserted in it comes out dry, 50 to 60 minutes. Remove the cake from the oven; immediately invert the pan and ...

Sponge cake batter is filled with tiny air bubbles from whipped egg whites and yolks. As the cake bakes, these air bubbles heat up and expand, lifting the cake to a light, spongy texture.