Melt chocolate in boiling water. Cool. Cream butter and sugar until fluffy. Add yolks 1 at a time, beating well after each. Blend in vanilla and chocolate. Sift flour with soda and salt;add alternately with buttermilk to chocolate mixture, beating after each addition until smooth. Fold in beaten whites. Pour into three 9-inch layer pans, lined on bottoms with paper. Bake at 350 for 30 to 35 minutes. Cool. Frost tops only. For COCONUT-PECAN FROSTING. Combine 1 cup evaporated milk, 1 cup sugar, 3 slightly beaten egg yolks, 1/2 cup butter and 1 teaspoon vanilla. Cook and stir over medium heat until thickened, about 12 minutes. Add 1 1/3 cups ANGEL FLAKE coconut and 1 cup chopped pecans. Cool until thick enough to spread, beating occasionally. Makes 2 1/2 cups.