That sure does sound like Buttercream. The Wilton recipe is very good; I did learn a couple of tricks in cake decorating class. If you can find it over there, Crisco makes shortening with no trans fat - that's the one I used, and it worked great. Add the salt; it cuts the sweetness of the frosting to 'just right'. I put mine in a stand mixer and beat it for about 10 minutes - that's how it got fluffy for me. (I took all 4 class courses, and my little hand mixer bit the dust during the first course.) I also split the flavoring with half vanilla and half butter flavor.
The recipe makes a lot, but you can store it in the fridge and just bring it to room temp when you want to use it again.
Now I'm hungry for cake :roll: :D