Rich Chocolate Frosting
["1/4 c. margarine", "2 1/2 c. sifted confectioners sugar", "3 egg yolks", "3 sq. melted unsweetened chocolate (3 oz.)", "1 tsp. vanilla", "1 to 2 Tbsp. hot water"]
["Cream margarine and sugar.", "Add egg yolks, beating after each. Stir in cooled melted chocolate.", "Blend in vanilla and add water until it is at spreading consistency."]
["margarine", "confectioners sugar", "egg yolks", "chocolate", "vanilla", "water"]