This recipe can be used to make Frozen Rainbow Chiffon Cake.
Bring 1/2 cup sugar, the water, and corn syrup to a boil in a saucepan, stirring until sugar dissolves. Continue to cook, without stirring, washing down sides of pan with a wet pastry brush to prevent crystals from forming, until mixture reaches 230 degrees on a candy thermometer.
Meanwhile, whisk egg whites with a mixer on medium speed until soft peaks form. Gradually whisk in remaining 2 tablespoons sugar. Immediately add sugar syrup in a slow, steady stream down the side of the bowl once it reaches 230 degrees. Raise speed to high, and whisk until mixture is thick, shiny, and cooled, about 7 minutes. Use immediately.
Food-safety note: The egg whites in this frosting are not fully cooked.