Description
This rich and creamy Roasted Garlic Potatoes au Gratin recipe features tender layers of thinly sliced starchy potatoes baked in a luscious cream sauce infused with roasted garlic, fresh thyme, and nutmeg, topped with a blend of Parmesan and Gruyère cheese for a golden, bubbly finish. Perfect as a comforting side dish to elevate any meal.
Ingredients
Potatoes
- 8-9 medium starchy potatoes (about 1.2kg), thinly sliced
Roasted Garlic
- 1 large head garlic, cut the top off
- Olive oil, for drizzling
- Pinch of salt, for seasoning garlic
Cream Sauce
- 1 cup (250 ml) heavy cream / double cream
- 1/4 cup (60 ml) whole milk
- 1 tablespoon unsalted butter
- 1 tsp fresh thyme leaves (or 1/3 tsp dried thyme)
- 1/4 tsp nutmeg
- Salt and pepper to taste
- 1/2 cup (40g) grated Parmesan cheese, divided
Topping
- 2 cups (about 220g) shredded Gruyère or mozzarella cheese
- Additional 1/4 cup grated Parmesan cheese (part of the divided amount above)
Garnish
- Fresh chives, for garnish
Instructions
- Preheat the Oven: Preheat your oven to 375°F (190°C) to ensure it is ready for roasting the garlic and baking the potatoes.
- Roast the Garlic: Cut the top off the garlic head to expose the cloves. Place it on a piece of aluminium foil, drizzle with olive oil, and season with a pinch of salt. Wrap it in the foil and roast in the oven for about 30 minutes until cloves are soft and golden. Let it cool slightly before handling.
- Prepare Baking Dish: Grease a 9×13-inch (23×33 cm) baking dish with butter and set aside for assembling the potatoes.
- Slice Potatoes: Peel and thinly slice the potatoes, ideally using a mandoline slicer for even thickness, which ensures uniform cooking.
- Layer Potatoes: Arrange the sliced potatoes upright in layers within the baking dish until all are used, creating a dense, vertical potato stack.
- Make Cream Sauce: In a saucepan over medium heat, combine the heavy cream, milk, butter, half of the grated Parmesan, thyme, nutmeg, salt, and pepper. Heat gently until butter melts and ingredients meld together, without boiling.
- Incorporate Roasted Garlic: Squeeze roasted garlic cloves from skins and mash into a paste. Stir this paste into the warm cream sauce until fully incorporated.
- Assemble and Cover: Pour the creamy garlic mixture evenly over the layered potatoes, making sure they are thoroughly coated. Cover the baking dish tightly with kitchen foil.
- First Bake: Bake the covered potatoes in the preheated oven for 1 hour and 15 minutes to allow the potatoes to cook through and absorb flavors.
- Add Cheese Topping: Remove the foil and sprinkle the shredded Gruyère or mozzarella and remaining Parmesan cheese evenly over the potatoes.
- Finish Baking: Return the dish to the oven uncovered and bake for another 15 minutes, or until the cheese topping is bubbly, golden brown, and the potatoes are fork tender.
- Rest and Garnish: Remove the dish from the oven and let it cool for a few minutes. Garnish with fresh chopped chives before serving to add color and fresh flavor.
Notes
- For best results, use starchy potatoes like Russet or Yukon Gold for creamy texture and good layering.
- Using a mandoline slicer helps ensure even cooking by keeping potato slices uniform in thickness.
- You can substitute Gruyère with mozzarella if you prefer a milder cheese flavor.
- Make sure not to boil the cream mixture; gentle heating preserves its richness and consistency.
- This dish can be prepared a day ahead and refrigerated; reheat uncovered in the oven before serving.
- Prep Time: 30 minutes
- Cook Time: 1 hour 30 minutes
- Category: Side Dish
- Method: Baking
- Cuisine: French
