Gratin dauphinois, the French sister of scalloped potatoes, must be the ultimate comfort food in winter. This superlative version was passed on to me by Chef Fernand Chambrette, a brilliant, cantankerous man whose cooking on a good day was legendary (don’t mention the bad days). The chef used to simmer the potatoes in milk to remove their tannin content, which would otherwise turn them brown and curdle the milk. The milk is then discarded, and the potatoes are cooked further in cream, this time to an inimitable, melting softness.

I really prefer my gratin dauphinois quite plain, but a little bit of garlic can be rubbed around the dish before adding the potatoes, or a few chopped chives can be stirred into them. For a more substantial dish, fry some diced bacon until crisp and add it to the potatoes before spreading them in the gratin dish. More importantly, be sure to use a floury potato for gratin dauphinois, such as an Idaho, and genuine Gruyère cheese – you’ll only need a bit, but it makes all the difference.

Serves 6-8
900 g-1 kg potatoes
1 quart/1 liter milk
375 ml/1½ cups heavy cream
375 ml/1½ cups crème fraîche, or more heavy cream
Salt and pepper
Large pinch of grated nutmeg
150 g/¾ cup grated Gruyère cheese
Butter for the baking dish
Medium baking dish  

1. Peel the potatoes and cut them in 5 mm/¼ inch slices – they are best sliced evenly using a mandolin slicer if you have one. Add them at once to the milk in a saucepan so they do not discolor. Bring them to a boil and simmer almost tender, 15-20 minutes (potatoes take longer to cook in milk than in water). Milk scorches easily, so use a heavy pan with the heat just at medium. Stir the potatoes quite often but take care not to crush them once they start to soften.

2. Drain the potatoes, discarding the milk and wipe out the pan. Return the potatoes to the pan with the heavy cream and crème fraîche. Season them to taste with salt, pepper, and nutmeg, and bring them just to a boil. Simmer until very tender, stirring occasionally, 10-15 minutes – if the potatoes boil, the cream will curdle.

3. Butter the baking dish and spread the potatoes and cream in it – the mixture will be quite sloppy. Sprinkle the top with the grated cheese. The potatoes can be prepared a day ahead and kept covered in the refrigerator.

4. To finish: Heat the oven to 350°F/175°C. Bake the gratin until very hot and browned on top, 25-30 minutes.