German Chocolate Cake
["4 oz. German sweet chocolate", "1/2 c. boiling water", "1 c. butter", "2 c. sugar", "4 egg yolks, beaten", "1 tsp. vanilla", "2 1/2 c. sifted cake flour", "1/2 tsp. salt", "1 tsp. baking soda", "1 c. buttermilk", "4 egg whites, stiffly beaten"]
["Melt chocolate in boiling water.", "Then cool.", "Cream butter and sugar until fluffy.", "Add egg yolks one at a time and beat well after each one.", "Add chocolate mixture and vanilla.", "Beat until light and fluffy."]
["sweet chocolate", "boiling water", "butter", "sugar", "egg yolks", "vanilla", "cake flour", "salt", "baking soda", "buttermilk", "egg whites"]