Use this frosting to make our Red Velvet Chocolate Cake.
In a small heavy saucepan, combine 1 cup sugar, corn syrup, and 1/3 cup water. Place over medium heat, and cook, stirring occasionally, washing down sides of pan with a wet pastry brush from time to time to prevent crystals from forming. Clip on a candy thermometer and stop stirring; increase the heat to high until temperature registers 235 degrees, about 7 minutes.
Whisk the egg whites in an electric mixer on medium speed, until soft peaks form, about 2 1/2 minutes. Gradually add remaining 2 tablespoons sugar. Remove syrup from heat, and pour in a steady stream down the side of the bowl containing the egg-white mixture, with mixer on medium-low speed. Increase speed to medium, and beat until cool, about 9 minutes. Add vanilla, and beat for 2 minutes more. Use immediately to frost cake.
To check if the sugar has dissolved, rub a bit of it between your fingers; you should not feel any grittiness.