German Sweet Chocolate Cake
["1 pkg. (4 oz.) Baker's German's sweet chocolate", "1/2 c. water", "2 c. all-purpose flour", "1 tsp. baking soda", "1/4 tsp. salt", "1 c. (2 sticks) margarine or butter, softened", "2 c. sugar", "4 egg yolks", "1 tsp. vanilla", "2 c. buttermilk", "4 egg whites", "Coconut-Pecan Frosting"]
["Heat oven to 350\u00b0.", "Grease and flour three 9-inch layer pans (you may use only 2 layers if you wish, baking time will be slightly longer.", "Heat chocolate and water on top of stove in a medium saucepan, stirring constantly until chocolate is completely melted.", "Mix flour with baking soda and salt; set aside.", "Beat margarine and sugar until light and fluffy.", "Add eggs yolks, one at a time, beating well after each addition.", "Stir in melted chocolate and vanilla.", "Add flour mixture alternately with buttermilk, beating after each addition until smooth.", "Beat egg whites until they form stiff peaks.", "Gently stir into batter."]
["chocolate", "water", "flour", "baking soda", "salt", "margarine", "sugar", "egg yolks", "vanilla", "buttermilk", "egg whites", "Coconut-Pecan Frosting"]