In a large skillet, fry bacon pieces; add onion and mushrooms and saute until soft; remove to plate. Add butter to skillet and brown chicken pieces. Layer chicken in removable liner, sprinkliing each layer with bacon, chopped onion, mushroom mixture. Combine remaining ingredients and pour over chicken. Place liner in base. Cover and cook on auto 4-5, low 6-8 hours or high 3-4 hours.