The gratin dish should be at least 5 cm high. Remove the peel from the potatoes and cut into very thin slices.
In a baking bowl, season with salt, pepper and a pinch of nutmeg (freshly grated). Mix well. Layer in the gratin dish previously rubbed with garlic. Add enough milk and cream so that the liquid reaches the edge but not over the potatoes. Sprinkle with butter flakes and bake in medium-hot oven (gas mark 4) for 2 hours. Add a tiny bit of milk if necessary.
When the potatoes are almost cooked after 3/4 of the cooking time, turn the temperature up, and sprinkle with grated Gruyère to crisp up the surface. Depending on the variety of potatoes, it can take up to 2 1/2 hours for the potatoes to cook through and through.
If you use very high fat milk from the country, you do not need crème fraîche for the potato casserole.
– Country : France – Region : Rhone-Alpes – Takes approx. : 02 h 20 min – Cooking time : 2 h – Preparation tz. : 20 min – Difficulty : Easy – Price : Medium