BASE:

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

FILLING:

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

FROSTING:

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

Heat oven to 350 degrees. Grease and lightly flour 9x13 inch pan. Melt butter and chocolate over low heat or in microwave. Stir in remaining base ingredients. Mix well. Spread in prepared pan.

In small bowl, combine all filling ingredients. Beat 1 minute at medium speed until smooth and fluffy. Spread over chocolate mixture. Bake 25-35 minutes or until toothpick in center comes out clean. Sprinkle with marshmallows and bake 2 minutes longer.

Meanwhile, in large saucepan, melt 1/3 cup butter, 2 oz. chocolate, milk and 2 oz. cream cheese over low heat. Remove from heat. Add powdered sugar and vanilla. Blend well. Immediately pour over marshmallows and swirl together. Chill until firm. Store in refrigerator.