This is one of my "favorite" tuna casserole recipes! It was Stacky5 at food.com who originally posted the recipe, but I did modify the recipe somewhat. I substituted one can of soup for another, plus I added a bit more of the macaroni. I really liked this dish reheated the next day in the microwave, as it was still nice and creamy!
Grease the inside of one 2-1/2 quart casserole baking dish; set dish aside.
Cook macaroni according to package directions to "al dente" (9 to 11 minutes). Once cooked, drain and rinse with cold water, then drain again.
While the macaroni is cooking, in a large bowl combine together, the soup, milk, and mayonnaise. Then stir in the shredded cheese, pepper, and tuna. (If desired, sprinkle in a bit of salt.)
Stir in the cooked macaroni, then pour the mixture in the casserole baking dish.
Sprinkle the bread crumbs evenly on top, then pour the melted butter over the bread crumbs.
Place casserole (uncovered) in a 350 degree oven, and bake for 30-35 minutes. (I baked mine for 35 minutes.)
Once heated through, remove from the oven and serve immediately.
*Note: Whenever I make this casserole, I always use Rotini pasta, and use 3 cups, which I cook anywhere from 10-11 minutes. Also, if I don't have a can of Fiesta Nacho Cheese Soup on hand, but have a can of cheddar cheese soup, I'll use that, and I'll only use a half soup can of milk, plus a half soup can of mild salsa. I'll also substitute shredded Mexican cheese for the cheddar.