Speedy Caramel Frosting
["1/2 c. butter", "1/2 tsp. salt", "2 1/2 c. powdered sugar", "1 c. brown sugar", "1/4 c. milk", "1/2 tsp. vanilla"]
["Boil butter, brown sugar, salt and milk.", "Blend in powdered sugar.", "Add vanilla.", "Spread on cooled cake."]
["butter", "salt", "powdered sugar", "brown sugar", "milk", "vanilla"]