Caramel Icing from Uncle Lou's Southern Kitchen

Place powdered sugar in a large bowl. Melt salted and unsalted butter in a small saucepan over low heat. Add brown sugar and cream, whisking until all lumps are dissolved. Bring to a boil over medium heat. Remove from heat; stir in vanilla.

Pour hot butter-cream mixture into powdered sugar; beat at high speed with an electric mixer 2 minutes or until blended. Cool 1 hour, stirring occasionally.