BAR:

1/2 c. butter
1 sq. (1 oz.) unsweetened chocolate
1 c. sugar
1 c. flour
1/2 - 1 c. chopped nuts
1 tsp. baking powder
1 tsp. vanilla
2 eggs

FILLING:

8 oz. pkg. cream cheese (reserve 2 oz. for frosting)
1/2 c. sugar
2 tbsp. flour
1/4 c. butter, softened
1 egg
1/2 tsp. vanilla
1/4 c. chopped nuts
6 oz. pkg. chocolate chips

FROSTING:

2 c. mini marshmallows
1/4 c. butter
1 sq. unsweetened chocolate
Remaining 2 oz. cream cheese
1/4 c. milk
3 c. powdered sugar
1 tsp. vanilla

Preheat oven to 350 degrees. Grease and flour 13 x 9 inch pan. In large saucepan over low heat, melt 1/2 cup butter and 1 ounce chocolate. Add remaining bar ingredients. Mix well. Spread in prepared pan. In small bowl, combine 6 ounces cream cheese with next 5 filling ingredients. Blend until smooth and fluffy. Stir in nuts. Spread over chocolate mixture. Sprinkle with chocolate chips. Bake 25 to 35 minutes or until toothpick comes out clean. Sprinkle with marshmallows and bake 2 minutes longer. In large saucepan over low heat, melt 1/4 cup butter, 1 ounce chocolate, remaining 2 ounces cream cheese and milk. Stir in powdered sugar and vanilla until smooth. Immediately pour over marshmallows and swirl together.