Creamy cheesy Potato Gratin for Two is simple to make and a perfect delicious meal for two.
Preheat your oven to 400°F and lightly grease your casserole dish. Layer half of the potatoes in the dish and top with the onions. Sprinkle with half of the salt and pepper, all of the flour, and half of the butter and cheese.
Add remaining potatoes and top with remaining salt, pepper, butter, and cheese. Pour milk and cream over the top.
Place a sheet of foil or baking sheet on the bottom rack to catch any milk or cheese that bubbles over. Bake gratin on the center rack for 40 to 60 minutes, until potatoes are fork tender.