1/2 c. butter
1 c. dark brown sugar, packed
1/4 tsp. salt
6 tbsp. milk
3 c. powdered sugar

Melt butter. Stir in brown sugar. Bring to boil and boil 2 minutes, stirring constantly. Remove from heat and add milk. Put back on heat and bring to full boil, again then set aside to cool 20 minutes. Stir in powdered sugar and beat until smooth. Best to sift powdered sugar.