This boiled icing recipe uses a small amount of corn syrup which speeds up the process a bit of creating a sugar syrup.
white corn syrup
Place corn syrup, sugar and water in a medium-sized saucepan. Stir until sugar dissolves.
Cook covered until the mixture comes to a boil.
In the bowl of an electric mixer, beat egg whites at high speed. While still beating, add 6 Tbsp. of the syrup mixture.
Continue cooking syrup mixture with the cover until the steam washes the sugar crystals down the sides. Remove the cover and place a candy thermometer into the the syrup. Cook until the mixture reaches 240 degrees F.
While still beating the egg whites, slowly add the remaining syrup to the egg whites. Add the vanilla. Continue beating for 4 minutes.