3 c. sugar
1 1/2 c. firmly packed brown sugar
1 c. milk
1 (8 oz.) pkg. unsweetened chocolate squares
3 tbsp. light corn syrup
1/3 c. butter
3 c. marshmallows
1 1/4 c. coarsely chopped walnuts

Grease 8-inch square pan. In heavy 4-quart saucepan, combine the sugars, milk, chocolate, and syrup. Heat to boiling over medium heat. Cook without stirring until 240 degrees on candy thermometer, or soft ball stage.

Remove fudge mixture from heat; stir in butter, marshmallows, and 1 cup nuts. Beat until fudge begins to get firm. Pour into greased pan. Sprinkle with remaining nuts. Refrigerate until firm.