Place sugar, milk, and salt in heavy saucepan. Place over medium heat and cook, stirring constantly, until all sugar is dissolved. Cover and cook to boiling. Remove cover and continue to boil to 240F (soft ball stage). Remove from heat and allow to cool until bottom of pan is warm to touch. Add butter and black walnut flavors and beat until creamy. Add chopped nuts. When stiff, pour into greased 8 inch square pan. Makes 48 pieces.
