1/2 c. butter
14 1/2 oz. can evaporated milk (do not substitute with sweetened condensed milk)
2 lbs. sugar (4 1/2 c.)
1/2 lb. marshmallows
2 oz. unsweetened chocolate
12 oz. pkg. semi-sweet chocolate or pieces
1 tbsp. vanilla
2 c. chopped nuts
3 bars (4 1/2 oz. each) sweet chocolate

Stir together in a large heavy pan or Dutch oven, over moderate heat, the butter, evaporated milk and sugar. Bring to a boil; cover, boil 5 minutes and turn off heat. Add marshmallows and stir until melted; add the chocolate, one kind at a time, stirring until melted. Add vanilla and nuts and mix well. Pour into buttered pan and smooth out evenly. This amount is exactly right for 10x15 jelly roll pan. Let stand until firm. Cut in 1 inch pieces.