3/4 cup brown sugar, 1/2 cup butter, 1 cup chopped walnuts, 1/2 cup semi sweet chocolate chips. Grease 9x9 pan. Spread nuts on bottom. Over high heat melt sugar and butter until boiling. Lower heat to medium. Boil for 7 minutes. Pour into pan. Sprinkle chips on top. Place a cookie sheet on top to retain heat and melt chips. Cut into squares while hot, then refrigerate until hard. Break into pieces.