The "Little Black Dress" Chocolate Cake

Like the legendary little black dress, this dessert is something I can’t live without, a mousse-y rich cake with a soft, oozing center (provided you don’t overbake it).

10 1⁄2 tablespoons unsalted butter
5 extra-large eggs
16 ounces top-quality semisweet chocolate, chopped
1 teaspoon vanilla extract, espresso powder, or orange zest

Preheat the oven to 375°F. Line the bottom of a 9-inch springform pan with parchment. Butter the sides of the pan with 1⁄2 tablespoon of the butter. Using an electric mixer, beat the eggs with a pinch of salt until tripled in volume, about 8 minutes. Melt the chocolate and the remaining 10 tablespoons butter slowly over low heat in a heavy medium saucepan; stir until smooth. Fold the chocolate mixture into the egg mixture with a flexible rubber spatula until completely incorporated. Add the vanilla. Pour into the pan.

Bake 18 minutes: The center will be quite soft. Cool 30 minutes.