So here we go...
- Equal amounts Butter (or Margarine) and Vegetable shortening, softened
- Icing Sugar
Cream shortening and butter together. And I mean really cream it, you shouldn't see any little butter clumps. The key, I find, to making icing "fluffy" is to mix thoroughly after each addition. Add in vanilla to suit your taste. If you want to color your icing later you don't really have to worry about having clear vanilla, but if you are wanting to leave it white then it is worth going out and finding it.