Crock Pot Chicken Cacciatore

1 medium onion (thinly sliced)
3 lbs boneless/skinless thighs and breasts
1 (6oz) can tomato paste
fresh mushrooms, sliced
2 bay leaves
1 (8oz ) can stewed tomatoes
salt and pepper to taste
1 tsp garlic powder
2 cups chicken stock

Directions:

Place sliced onions in bottom of crock pot; add chicken. Stir together remaining ingredients and pour over chicken. Cook on low 7-9 hours or high 3-4 hours. Serve over rice or pasta.