10 oz. semi-sweet chocolate chips
7 tbsp. unsalted butter
7 lg. eggs, separated
1/3 c. sugar

Melt chocolate with butter in top of double boiler, stirring frequently. Pour into large bowl and cool at room temperature.

In another bowl beat egg whites until foamy. Add sugar and beat until stiff. Beat egg yolks and stir into chocolate mixture. Fold in whites.

Pour into greased and floured 9 inch springform pan or 9 inch round pan. Bake at 250 degrees for 1 1/4 hours. Let cool 10 minutes and run knife around. Cool completely, flip cake on plate and sprinkle with powdered sugar.