chocolate mixture, then fold in remaining whites. Pour batter into greased and floured 10 or 12 inch springform pan. Bake in preheated 250 oven 2 1/2 hours. (That's what is says, two and one-half hours.) Cool completely on rack before removing pan. Sprinkle cake with powdered sugar. Serve with whipped cream. Serves 10 to 12.