1/2 c. butter
1 lb. light brown sugar
1 lb. confectioners sugar
1/2 c. milk
3/4 c. smooth or crunchy peanut butter
1 tsp. vanilla extract

In medium saucepan, melt butter and stir in brown sugar and milk. Bring to a boil; boil and stir 2 minutes. Remove from heat; stir in peanut butter and vanilla. Mix confectioners sugar and beat until smooth. Spread into buttered 9-inch square baking pan. Chill until firm. Cut into squares.