This dreamy marshmallow frosting is a new family favorite. Unlike many 7-Minute Icings, this is a no-cook method. The trick is using boiling water to “cook” the meringue. Add 50 grams sugar, 1 egg white, and tiny tilt of vanilla extract to a deep bowl. Beat on medium-high speed, until it thickens a bit, and begins to look glossy. With the mixer on medium-high speed, drizzle in 1 1/2 tablespoons boiling water. Increase the speed to high, and beat for 5 minutes until glossy, stiff peaks form when you lift the beaters from the bowl.