Gratin Savoyard

Set the oven at hot (200°C/400°F). Cut the potatoes in very thin slices, using a mandoline cutter if possible. Don’t soak them in water as this removes some of the starch needed to bind the gratin. Spread a layer of potato slices in the buttered baking dish and sprinkle them lightly but evenly with salt, pepper, nutmeg and some of the grated cheese. Continue making layers until all the potatoes