Lima Bean Casserole

1 (10 ounce) package frozen lima beans
1 can Cheddar cheese soup
1/2 cup milk
3/4 cup chopped celery
1/4 cup chopped parsley
1 (3 ounce) can French-fried onion rings, divided

Cook lima beans; drain. Combine lima beans, soup, milk, celery and parsley. Mix in half of onion rings. Bake at 350 degrees F for 35 minutes. Sprinkle with remaining onion rings and bake 10 minutes.