3 (6 oz.) pkgs. Nestle's semi-sweet chocolate bits
2 tbsp. butter
2 c. marshmallows
2 c. raisins (opt.)
1 c. broken walnuts

Melt bits with butter in double boiler. When fully melted, add remaining ingredients. Grease 8 x 8 x 2 inch pan. Chill in refrigerator for 1 1/2 to 2 hours. Cut into squares.