Creating Roasted Garlic Potatoes au Gratin is an art, but with these simple steps, you’ll master it in no time:

1. Preheat Oven: Begin by setting your oven to 375°F (190°C).
2. Roast Garlic: Wrap the head of garlic in foil, drizzle with olive oil, and add a pinch of salt. Roast for 30 minutes until the garlic is soft and fragrant.
3. Prep Dish: Grease a 9×13-inch baking dish generously with butter.
4. Slice Potatoes: Peel and thinly slice the potatoes using a mandoline for uniformity.
5. Layer Potatoes: Arrange the potato slices upright in the prepared baking dish, ensuring they are tightly packed.
6. Make Cream Mixture: In a saucepan, combine the heavy cream, milk, butter, half of the grated parmesan, thyme, nutmeg, salt, and pepper. Heat the mixture gently until the butter is melted, but do not bring it to a boil.
7. Add Garlic: Squeeze the roasted garlic into a paste and stir it into the cream mixture, blending thoroughly.
8. Combine: Pour the creamy garlic mixture over the arranged potatoes, ensuring they are covered evenly. Cover the dish with foil.
9. Bake: Place the dish in the oven and bake for 40 minutes. Then, carefully remove the foil.
10. Add Cheese: Sprinkle the remaining cheese on top of the potatoes. Continue baking uncovered for an additional 30 minutes until the top is bubbly and golden brown.
11. Serve: Allow the dish to cool for a few minutes. Garnish with freshly chopped chives and serve hot.