Prepare the potatoes:Peel and thinly slice the potatoes (about 2–3 mm thick). You can use a mandoline for even, delicate slices that cook perfectly.

Infuse the milk:Pour the milk into a saucepan, add salt, pepper, and a pinch of nutmeg. Warm it gently over medium heat until it’s just about to simmer. Don’t boil it — you just want the flavors to combine.

Cook the potatoes:Add the sliced potatoes into the warm milk mixture and let them cook gently for 8–10 minutes. Stir occasionally so the milk doesn’t scorch. The potatoes should begin to soften but not fully cook through.

Prepare the garlic and butter:While the potatoes are simmering, melt the butter in a small pan and sauté the minced garlic until fragrant. This adds a delicious depth to the gratin’s creamy flavor.

Assemble the gratin:Preheat your oven to 180°C (350°F). Butter a baking dish generously. Pour half of the potato mixture into the dish, spreading it evenly. Drizzle with some garlic butter and sprinkle a handful of cheese. Add the remaining potatoes and pour over the rest of the milk mixture. Finish with the remaining cheese on top.

Bake the gratin:Place the dish in the preheated oven and bake for 25–30 minutes, or until the top is golden and bubbling and the potatoes are tender when pierced with a knife.

Garnish and serve:Once baked, let the gratin rest for 5–10 minutes before serving. Sprinkle chopped parsley over the top for a fresh finish. Serve warm and enjoy the irresistible combination of creamy layers and a crispy, cheesy crust.