1: Peel and wash 1 kg potatoes. Slice evenly (a mandolin is ideal for this), and wash again.
2: In a large saucepan over medium heat, pour in 1 litre whole milk, salt and add 1 bayleaf, 1 sprig thyme, 1 garlic clove. Pour in the sliced potatoes.
3: Cook until tender.
4: Remove and discard thyme, bay leaf and garlic, then drain the potatoes. Tip: Save the milk for a later recipe, such as a béchamel sauce, or another gratin.
5: Grate 50 g Comté cheese and 50 g Mimolette, set aside. Preheat oven to 200°C (390°F).
14: Bake at 200°C (390°F) for around 30 minutes, watching for browning at the end.
Remarks
The cheeses listed can be replaced according to your taste, and what you have on hand, but I recommend finishing with a hard cheese (like Comté) on top, as your gratin will brown more easily. The proportions of cream and cheese given are indicative, so feel free to adapt them to your taste.