paper or waxed paper. Pour boiling water over chocolate, stirring until chocolate is melted; cool. Mix sugar and margarine in medium bowl until light and fluffy. Beat in egg yolks, one at a time. Beat in chocolate and vanilla on low speed. Mix flour, baking soda and salt. Add alternately with buttermilk, beating after each addition until batter is smooth. Fold in egg whites. Divide batter between pans. Bake 8-inch squares 45-50 minutes, 9-inch squares 40-45 minutes, 8-inch rounds 35-40 minutes, 9-inch rounds 30-35 minutes or until wooden pick inserted in center comes out clean. Cool cakes 10 minutes. Invert on wire rack and cool completely. Fill layers and frost top of cake with Coconut-Pecan Frosting. Coconut-Pecan Frosting. Beat egg yolks and milk in 2-quart saucepan. Stir in sugar, margarine and vanilla. Cook over medium heat about 12 minutes, stirring occasionally, until thick. Stir in coconut and pecans. Beat until frosting is of spreading consistency. From. Betty Crocker's Cookbook. ----