stir everything together. top with some cheese. bake at 350F for one hour. ~the entire casserole can be made in advance then baked right before eating!
for gluten free, choose a gluten free creamy canned soup. for vegetarian, choose cream of mushroom or cream of cheese soup. choose a 2-3 quart baking dish; the equivalent of an 8x8 baking dish. don't overthink it.