Beat cream cheese, butter, marshmallow crème, and vanilla at medium speed with an electric mixer until creamy. Gradually add powdered sugar, beating at low speed until blended and smooth.
I'll begin by saying I haven't tried this yet but good old 7 minute frosting works great! Kinda marshmellowey and inexpensive! Don't need the orange liqueur in the recipe on this site for seven minute frosting, but it sounds good.