Caution: This makes a large batch. For one cake or cupcakes/cookies, quarter the recipe.
1 cup shortening or butter, whip well
1-2tsp vanilla
7 cups confectioner's sugar
dash of salt
add milk (1/4 cup or so to thickness needed)
If you want to make it chocolate, remove the same amount of sugar you add into the mix...
Last time I made this though, I didn't do that and it came out fine. I have had this with shortening, and I've had it with butter. Personally I prefer it with butter, but it comes out fine either way.