Preheat oven to 350 degrees F (175 degrees C). Grease one 9x9 inch pan.
In a heavy skillet, melt 8 tablespoons butter over low heat. Saute the onion and peppers until soft. Place sausage in skillet; crumble and cook over medium high heat until evenly brown. Drain, and transfer to a large bowl.
Combine sausage mixture with stuffing mix, bread crumbs, chicken stock, egg, and salt and pepper. Mix well, and transfer dressing to prepared pan. Dot with remaining butter.