Squash Casserole

2 pounds (6 cups) yellow summer squash or green zucchini squash, sliced
1/4 cup chopped onion
1 can condensed cream of chicken soup
1 cup dairy sour cream
1 cup shredded carrots
1 small jar pimentos
1 8 ounce package herb-seasoned stuffing mix
1/2 cup butter or margarine, melted
4 ounces shredded sharp cheddar cheese

Cook sliced squash, chopped onions and carrots in boiling salted water for 5 minutes; drain. Combine cream of chicken soup, sour cream, pimentos. Fold in drained squash, onion, 3/4 of the cheese, melted margarine and stuffing mix. Spoon the vegetable mixture into a greased baking dish. Sprinkle the remaining cheese on top of the casserole. Bake at 350 degrees for 25-30 minutes or until heated through.