so that one's really going for incorporation of air - interesting! and adds vanilla, where royal adds lemon juice. What does the cream of tartar do?I have a recipe for a frosting that is like this one but does not get hard
Fluffy White Frosting
1C White sugar
1\3 C water
1\4 tsp cream of tartar
2 Egg Whites
1 tsp vanilla
In a large saucepan, stir together sugar water and cream of tartar. Cook over medium high heat until the sugar dissolves and mix is bubbly. Set aside to cool.
In a medium mixing bowl, whip the egg whites and vanilla to soft peaks using a mixer. Gradually add the sugar mixture while whipping constantly until stiff peaks form, about 7 to 10 minutes. Frost the cake of your choice.