1/2 c. butter
1 sq. unsweetened chocolate or 1 env. pre-melted chocolate
1 c. sugar
1 c. flour
1/2 - 1 c. nuts
1 tsp. baking powder
1 tsp. vanilla
2 eggs

FILLING:

8 oz. cream cheese (softened, 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. semi-sweet chocolate chips

FROSTING:

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

Preheat oven to 350 degrees. Grease (not oil) and flour a 13x9 pan.

In large saucepan over low heat, melt 1/2 cup butter and 1 ounce chocolate. (Lightly spoon flour into measuring cup; level off.) Add remaining bar ingredients. Mix well. Spread into prepared pan.

In small bowl, combine 6 ounce cream cheese with next 5 ingredients. Beat 1 minute at medium speed until smooth and fluffy. Stir in nuts. Spread over chocolate mixture. Sprinkle with chocolate pieces. Bake for 25-35 minutes. Remove from oven, sprinkle with marshmallows. Bake 2 minutes longer.