Meringue Topping
Beat egg whites until soft peaks form; gradually add sugar and optionally cream of tartar, and beat until the mixture forms stiff peaks.
Spoon the meringue onto the top of pie, pudding, etc., being careful to completely cover it. Bake in a medium oven (350° F) 10-12 minutes or until the meringue is delicately browned.
Be careful when separating the eggs - if more than a tiny bit of yolk gets into the whites, the meringue will not work! The egg yolk will prevent peaks from forming.
Cream of tartar and vanilla extract are optional in this recipe. The cream of tartar helps to stabilize the meringue so that it holds the peaks better, but you can make meringue without it. A little lemon juice (about 1/2 tsp.) will help to stabilize the meringue too, and would be good if you are topping a lemon pie, but it doesn't work as well as cream of tartar for stabilizing the meringue.
Vanilla extract can be added if it will complement the dessert you are topping - I think it would go well with a chocolate pie, for example.