Boil noodles in a large pot for about 9 minutes. Meanwhile, grease a casserole dish with butter or margarine. Once noodles are cooked and drained, add the mushroom soup, milk, and tuna to the noodles either in a mixing bowl or you can combine in the casserole dish.

Place the cheese slices or shredded cheese on top.

Bake in a 350F oven for 20 minutes.