Simple au gratin potatoes

We tried this recipe, which calls for cheddar cheese: https://www.tasteofhome.com/recipes/simple-au-gratin-potatoes Our modifications: first, we halved this recipe but found a 2-quart casserole dish to be the right size (a larger casserole dish may be needed for the full recipe). Second, we rubbed the inside of the casserole dish with a smashed garlic clove, then lightly sprayed the inside of the dish with oil. Finally, we used a shallot (thinly sliced crosswise) and added the garlic clove (which we minced) to the sauce. (June 2018)