- 7 ounces bittersweet chocolate , coarsely chopped
- 1/2 cup unsalted butter , cut up
- 1 cup sugar
- 2 tablespoons flour , plus more for pan
- 4 eggs , separated
Whisk sugar and flour into chocolate mixture, then whisk in egg yolks. In a large mixing bowl, beat egg whites until stiff. Fold beaten whites into chocolate mixture until just blended. Pour batter into prepared pan. Bake 30 minutes or until a cake tester inserted into center comes out clean.
Cool completely and cut into squares.