Mountain Frosting

Stir sugar, corn syrup, and water in a small heavy saucepan over high heat. Set spoon aside.

Using a pastry brush dipped in water, wash down any sugar crystals from the sides of the pan.

Heat mixture to a rolling boil without stirring until a candy thermometer reaches approximately 242 degrees Fahrenheit.

As sugar syrup is boiling, beat egg whites in the bowl of an electric mixer using the whip attachment at high speed until stiff peaks form.

Slowly pour hot syrup into the bowl of whites, beating the egg whites constantly.

Beat on high speed for approximately two minutes until stiff peaks form.

Add vanilla and mix until well blended.

Use immediately or store, covered in refrigerator.