Meringue Frosting (ghiacciata Miringhe)

Combine sugar and water in a saucepan, and cook over medium flame until syrup spins a long thread from the tip of spoon. Remove from heat and add vanilla. Set pan in cold water and while syrup is cooling, beat egg whites until stiff but not dry. Add beaten egg whites to syrup and beat constantly until mixture becomes a smooth paste. Tint with 4 drops of food colouring, if desired. This frosting may be used as decorative icing or to make meringues, tarts, or pies.