Double Boiler Frosting
["2 egg whites (1/4 c.)", "1 1/2 c. sugar", "1/4 tsp. cream of tartar or 1 Tbsp. light corn syrup", "1/3 c. water", "1 tsp. vanilla"]
["Combine egg whites, sugar, cream of tartar and water in top of double boiler.", "Beat at high speed 1 minute.", "Place over boiling water; beat on high speed 7 minutes.", "Remove pan from boiling water; add vanilla.", "Beat 2 minutes longer on high speed.", "Fills and frosts two 8 or 9-inch layers or frosts a 9 x 13-inch cake."]
["egg whites", "sugar", "cream of tartar", "water", "vanilla"]