1 cup butter, softened
1 cup confectioners' sugar
6 tablespoons milk
3 tablespoons cornstarch
2 cups heavy whipping cream
1 tablespoon vanilla extract
In wide bowl, whip cream until stiff peaks form. Stir in sugar; continue whipping until stiff peaks form, about 10 minutes. Beat in milk, whipping cream mixed with remaining confectioners' sugar until smooth. Fold in cornstarch; stir into creamed mixture. Chill in refrigerator until serving (room temperature may be an issue); refrigerate frozen or refrigerate in freezer. Spread frosting on carton of ice.