In a non-stick skillet, cook sausage over medium heat until lightly browned. Add prepared beans to skillet; remove from heat. In a small bowl, combine soup and sour cream. Pour over sausage mixture and stir gently. In a bowl, combine stuffing mix and butter. In a greased 2-1/2 quart baking dish, spoon one-half of stuffing mixture; cover with sausage mixture. Top with remaining stuffing mixture. Drizzle with chicken stock. Bake, covered, at 350°F for 25-30 minutes or until heated through. Serve.