Using a mixer, blend together cream cheese, butter, and vanilla. Gradually mix in confectioners' sugar and then mix in 1/2 the chocolate chips.
Spread evenly in a 9" pie plate. Cover with marshmallows and remaining chocolate chips.
Bake at 350 degrees for 15-18 minutes or until marshmallows are toasted to a golden color. Keep a close eye toward the end of the baking time as the marshmallows will easily burn.
Serve with graham crackers.