Buttercream Dream Icing... This recipe for buttercream icing is without a doubt the absolutely best Buttercream icing I’ve ever found. And it’s really pretty simple. It’s just butter, shortening, clear vanilla extract, confectioner’s sugar and milk. But don’t let the simplicity fool you into thinking this is just an ordinary, run-of-the-mill buttercream. The end results is positively fantastic!.