Sounds like a great icing for Carrot Cake!
I make Marshmallow Buttercream for icing my cupcakes.
Marshmallow Creme Buttercream
- 1lb (4sticks) of unsalted butter, softened 2 jars or tubs (7 or 7 1/2 oz each) or 1 large tub (16 oz) marshmallow cream (such as Marshmallow Fluff or Creme) 2 cups confectioners' sugar 2 tsp vanilla (I had to reduce to 1 tsp b/c the vanilla flavor was overpowering w/ 2 tsp) you could also sub another flavoring for the other tsp.
Beat butter in a large bowl w/mixer on medim speed until creamy. Beat in marshmallow cream. When well blended, beat in confectioners' sugar and vanilla. Increase speed to high and beat 3 to 4 min until fluffy.