Boiled Frosting 2 C granulated sugar 1/3 C Water 1/3 C Corn syrup 2 Egg whites 1 tsp Maple extract Combine sugar, corn syrup and water in top of double boiler. Cook over boiling water until syrup will spin a long thread when dropped from a spoon or untilcandy thermometer reads 238 degrees. Remove from heat. Meanwhile, have ready stiffly beaten egg whites. Add the beaten egg whites and vanilla and beat until mixture is almost cold, becomes creamy and will hold its shape when spread on cake. Use immediately.