Grease an appropriately sized baking dish or casserole dish with the butter. Place a layer of sliced potatoes on the bottom and sprinkle with 1/4 of the cheese. Repeat this process until all the potatoes have been layered, top with the remaining cheese.
Pour the cream over top and gently shake to distribute the liquid evenly.
Cover the pan with aluminum foil and bake until the potatoes are tender, about 30 minutes. The sauce should be nice and bubbly around the edges. Then remove the foil and bake uncovered for another 10 minutes, or until the potatoes are cooked through.
Remove the dish from the oven and let it sit for 5-10 minutes before portioning and serving.