Instructions

Melt chocolates and butter together. Beat eggs yolks and sugar until very thick and lemon colored. Fold into chocolate mixture. Beat egg whites and cream of tartar until soft peaks form. Gently fold chocolate/egg mixture (1/3 at a time) into whites, just until blended. Scrape into greased springform pan. Bake at 300 for 35 min. Cool completely. Refrigerate overnight in pan. Serve at room temp. Dust with powdered sugar.