2 cups very cold heavy cream
1 1/4 cups sifted confectioners' sugar
4 ounces very finely grated semi sweet baking chocolate
6 egg whites
Whip the cream. Before it begins to stiffen and while it is still the consistency of buttermilk, add the confectioners' sugar a little at a time and continue whipping. When all the sugar has been incorporated and the cream is stiff enough to hold peaks, mix in the grated chocolate. Beat the egg whites until they are stiff but not dry; fold them into the cream and chocolate mixture. Line a loaf pan of 1 1/2 to 2 quarts with wax paper and pour the mixture into the pan. Cover with plastic wrap and freeze overnight. To serve, unmold the loaf onto a platter, remove wax paper and slice.