Glossy Chocolate Frosting Melt 6 ounces (6 squares) of unsweetened chocolate. Add 1/2 cups of sifted confectioners' sugar and 5 tablespoons of hot water. Beat well, add 1 1/2 cups more of sugar. Gradually beat in  6 egg yolks. Once smooth and blended, beat in 1/2 cup of soft butter or margarine. Makes enough frosting for tops and sides of three 8 inch layers.