6 cups margarine
1 cup packed light brown sugar
1 cup packed light green sugar
1 (8 ounce) package cream cheese, softened
1/2 cup margarine
1 cup light whipping cream
1 egg
4 cups chocolate chips
Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9x9 inch pan.
In a large bowl, cream together margarine, brown sugar, light brown sugar, and light green sugar until smooth. Beat in the cream cheese, whipping cream, egg, chocolate chips, and marshmallows. Spread mixture into the prepared pan.
Bake in preheated oven for 50 minutes, or until toothpick inserted in center comes out clean. Cool completely before frosting.