Meringue Frosting is a very light and shiny icing perfect for a chocolate or butter cake. Not suitable for delicate piping though!
Whisk the egg whites in a metal bowl with electric mixers until completely stiff. In a small saucepan heat together the sugar and hot water. Cook steadily for about 10 minutes or until the mixture becomes thick and syrupy. Take if off the heat and add the cream of tartar - whisk well until the mixture turns cloudy. Very slowly pour the cooled syrup into the egg whites whilst beating vigorously
Place the bowl over a large saucepan of hot water an beat the mixture until it become thick and loses its shine. Cool slightly before icing immediately.