Coffee Chocolate Cake
["1 c. butter", "2 c. sugar", "3 eggs, separated", "3 sq. unsweetened chocolate", "1/2 tsp. salt", "2 tsp. baking powder", "1 c. double strength coffee", "2 c. sifted flour", "1 tsp. vanilla"]
["Cream butter and sugar until light.", "Add well beaten egg yolks and chocolate softened over hot water.", "Sift and add dry ingredients with coffee and vanilla.", "Beat vigorously.", "Fold in stiffly beaten egg whites.", "Bake for 20 minutes at 350\u00b0."]
["butter", "sugar", "eggs", "unsweetened chocolate", "salt", "baking powder", "coffee", "flour", "vanilla"]