Preheat your oven to 375 degrees.
Cook your egg noodles according to the directions and strain when they are done.
Mix together the cream of chicken, mayonnaise, and milk together in a large bowl.
Next, add the diced celery and onion to your mixture.
Add next, strain the tuna and add to the bowl.
After mixing add in the cooked and strained egg noodles.
Finally, after everything is well mixed in add in the amount of cheese if you want.
Spray casserole pan and place in a 9X13 pan spray with nonstick and spread out the mixture.
Salt and pepper to your taste, and add in other seasonings if you want to.
Top with crushed corn flakes, or you can skip these.
Cook at 375 degrees for about 40-45 minutes, just until the top starts to brown.
Other Ingredients For Tuna Casserole: