Party Potato Casserole

Ingredients:
- 2 (10 3/4 oz. each) cans cream of celery soup
- 1 (8 oz.) carton dairy sour cream or unflavored yogurt
- 1 (32 oz.) bag frozen hash brown potatoes *
- 1 medium onion, chopped
- 3 Tbsp. diced pimento
- 2 tsp. salt
- 1 green pepper, chopped
- 1/8 tsp. pepper
- 1/4 c. grated Parmesan cheese (optional)

Directions:
- *Eight cups of cubed potatoes (about 8 medium) can be substituted for the frozen potatoes.