This is a great variation to Tuna Casserole that my SIL sent to me back in the 90's. I've substituted Cream of Mushroom Soup for the Cream of Celery and it works fine. Also, the original recipe called for American cheese but I've found that Cheddar is better. I've made it many times, it is easy to prepare and makes a great meal with a salad and garlic toast.