German Chocolate Cake
["1 package sweet German chocolate", "1/2 cup boiling water", "2 sticks butter", "2 cups sugar", "4 egg yolks, unbeaten", "1 tsp. vanilla", "2 1/2 cups sifted cake flour", "1 tsp. baking soda", "1/2 tsp. salt", "1 cup buttermilk", "4 egg whites, beaten stiff"]
["Preheat oven to 350\u00b0. Melt the chocolate in the boiling water and let cool. Cream the butter and sugar until light. Add the egg yolks one at a time, beating after each. Add the vanilla and chocolate. Mix until blended. Sift together the flour, baking soda, and salt. Add the flour mixture to the butter mixture, alternately with milk, beating after each addition. Fold in the egg whites. Pour into three greased and floured round cake pans. Bake at 350\u00b0 for 35 to 40 minutes."]
["chocolate", "boiling water", "butter", "sugar", "egg yolks", "vanilla", "cake flour", "baking soda", "salt", "buttermilk", "egg whites"]