Granny's 7-Minute Icing

If you look, you'll find a lot of icing recipes on the internet, but this is the one my grandmother used. I think it was her go-to recipe for Orange Cake and Coconut Cake.

Ingredients

1 cup sugar
¼ tsp salt
½ tsp cream of tartar
2 egg whites
3 tbsp. water
1 tsp vanilla

Combine all ingredients except vanilla in a stainless steel heavy-bottomed sauce pan.
Place over medium heat and beat with an electric hand mixer constantly for 5-7 minutes, or until icing is fluffy and stiff peaks form when beaters are removed. WARNING: be very careful with this step, you are essentially using a hand mixer to make edible napalm.
Remove from heat and stir in vanilla.
Ice cake.

It takes two batches of this recipe to ice a layer cake.