8 ounces semisweet chocolate
1/4 cup water
8 large eggs, separated
1 teaspoon vanilla extract
Pinch of salt
2/3 cup granulated sugar
1. In the top of a double boiler set over barely simmering water, melt the chocolate and water, stirring occasionally (about 10 minutes). Remove from the heat and beat in egg yolks, 1 at a time. Stir in the vanilla and salt.
2. Beat the egg whites until soft peaks form. Gradually add the sugar, beating until stiff and glossy (3 to 5 minutes). Fold ¼ of the egg whites into the chocolate mixture, then gently fold in the remaining whites.
3. Pour into a bowl or individual serving dishes, cover, and chill until set (at least 4 hours).
CHOCOLATE MOUSSE PIE: Preheat oven to 350° F. Grease a 9-inch pie pan and dust with sugar. Pour 4 cups of mousse (above) into prepared pan, reserving remaining mousse in refrigerator. Bake until set (about 25 minutes). Cool for 30 minutes, then chill. (Center will fall, forming a shell.) Pour reserved refrigerated mousse into chocolate shell. Refrigerate until serving time.
JELLY ROLL MOUSSE CAKE: Preheat oven to 350°F. Spoon 4 cups of mousse into a 15 ½- by 10½-inch jelly roll pan lined with parchment paper. Bake until firm (about 15 minutes). Transfer to a rack and let cool. Invert onto a piece of parchment paper placed on a flat surface, peel off the paper, and spread with the remaining mousse. Roll up from a long end. Refrigerate until needed. Slice and serve.