Creamy Garlic Potato Gratin Dauphinois With Gruyère

Why You’ll Love This Recipe

• Classic French comfort food: ultra-creamy potatoes with a luxe layer of melted, browned Gruyère.
• Simple, accessible ingredients, but the result feels restaurant-worthy and special.
• Perfect make-ahead side for holidays, dinner parties, or any cozy weekend meal.
• Reliable, step-by-step method for evenly cooked potatoes and a perfectly golden top every time.

Grocery List

• Produce: 2.25 lb (1 kg) potatoes, 2 large garlic cloves, optional fresh thyme or chives for garnish
• Dairy: Heavy cream, whole milk, Gruyère cheese, unsalted butter
• Pantry: Fine sea salt, black pepper, whole nutmeg (or ground), optional olive oil spray or extra butter for greasing

Full Ingredients

For the Gratin Dauphinois

• 2.25 lb (1 kg) potatoes, peeled (waxy or all-purpose such as Yukon Gold, Charlotte, or similar)
• 2 cups (480 ml) heavy cream
• 1 cup (240 ml) whole milk
• 2 cups (about 7 oz / 200 g) Gruyère cheese, coarsely grated
• 2 large garlic cloves, divided (1 whole, 1 finely minced)
• 2 tbsp unsalted butter, softened (plus a little extra for greasing if needed)
• 1 tsp fine sea salt, plus more to taste
• 1/2 tsp freshly ground black pepper, plus more for topping
• 1/4 tsp freshly grated nutmeg (optional but traditional)

Optional Garnishes

• 1–2 tsp fresh thyme leaves or finely chopped fresh chives
• Flaky sea salt, to finish

Step-by-Step Instructions

Step 1: Preheat the oven and prep the dish

Preheat your oven to 350°F (175°C) with a rack in the middle. Choose a 2-quart (about 2-liter) shallow gratin dish or baking dish; an oval or rectangular dish roughly 8×11 inches or 9×9 inches works well. Peel one garlic clove, slice it in half lengthwise, and rub the cut side all over the bottom and sides of the dish to lightly perfume it with garlic. Discard the clove. Using your fingers or a pastry brush, generously coat the inside of the dish with the 2 tablespoons of softened butter, making sure to get into the corners so the potatoes do not stick.

Step 2: Make the garlic-infused cream

Finely mince the second garlic clove. In a medium saucepan, combine the heavy cream, whole milk, minced garlic, 1 teaspoon fine sea salt, 1/2 teaspoon black pepper, and the grated nutmeg (if using). Place over medium-low heat and warm gently, stirring occasionally, until the mixture is steaming and small bubbles form around the edges, 3–5 minutes. Do not let it come to a boil, or it may separate. Once warmed and fragrant, turn off the heat and let it sit while you slice the potatoes. This brief steeping helps infuse the cream with garlic and spice.

Step 3: Slice the potatoes very thin

Peel the potatoes and immediately place them in a bowl of cold water to minimize browning while you work. One at a time, slice the potatoes into very thin rounds, about 1/8 inch (3 mm) thick. A mandoline makes this quick and ensures even slices, but a sharp chef’s knife works well if you take your time. Try to keep the slices as uniform as possible; this ensures that the layers cook evenly and become tender at the same time. After slicing, pat the potatoes dry with a clean kitchen towel or paper towels to remove excess surface moisture; this helps the cream cling to the potatoes and prevents the gratin from becoming watery.

Step 4: Build the first potato and cheese layer

Arrange half of the sliced potatoes in the prepared dish in an overlapping shingle pattern: start at one end and fan the slices slightly, working your way across and then up the dish. This looks pretty and also prevents gaps. Once you have a full, even layer (about half the potatoes), gently stir the warm cream mixture and pour roughly half of it over the potatoes, making sure to distribute the garlic and seasoning. Tap the dish lightly on the counter to help the cream settle between the slices. Sprinkle half of the grated Gruyère (about 1 cup) evenly over the potatoes. Lightly season the surface with a small pinch of salt and pepper, keeping in mind that the cheese is already salty.

Step 5: Add the second layer and finish assembling

Arrange the remaining potatoes on top in the same overlapping pattern, creating a second even layer. Pour over the remaining warm cream mixture, again distributing it evenly. Gently press down with your hands or the back of a spatula to compact the layers and ensure the potatoes are mostly submerged in liquid. Sprinkle the remaining Gruyère across the top in an even layer. If any potato edges are sticking well above the cream, tuck them down slightly; exposed edges can get too dark before the center is fully cooked. Finish with a light grind of black pepper on top for color and flavor.

Step 6: Bake until tender, bubbling, and deeply golden

Cover the dish tightly with aluminum foil, tenting it slightly so it does not press against the cheese. Place the gratin on a baking sheet (to catch any drips) and bake for 40 minutes. Remove the foil carefully to avoid steam burns, then continue baking uncovered for 25–30 minutes more, until the top is deeply golden, the cream is bubbling around the edges, and a knife slides into the center with no resistance. Total baking time is about 65–70 minutes, depending on your oven and the exact thickness of your slices. If the top is not as browned as you like once the potatoes are fully tender, you can increase the oven temperature to 400°F (200°C) for the last 5–8 minutes, watching closely so it does not burn.

Step 7: Rest, garnish, and serve

Once the gratin is cooked, remove it from the oven and let it rest on a heatproof surface for 10–15 minutes. This resting time allows the cream to thicken and the layers to set slightly, so the gratin spoons out in beautiful, cohesive servings instead of sliding apart. Just before serving, sprinkle the top with fresh thyme leaves or chopped chives, if using, and a pinch of flaky sea salt for a delicate crunch. Serve warm, scooping down through all the layers so everyone gets tender potatoes, rich garlic cream, and plenty of bronzed Gruyère from the top and edges.

Pro Tips

• Go for even slices: A mandoline is ideal for 1/8 inch (3 mm) slices, but if you slice by hand, take your time. Even thickness is the secret to evenly cooked potatoes.
• Do not rinse after slicing: Once the potatoes are sliced, avoid rinsing them again; you want some of the natural starch to help thicken the cream and bind the layers.
• Use full-fat dairy: Heavy cream and whole milk give the creamiest, most stable sauce. Lower-fat milk can curdle or turn watery in the oven.
• Mind the seasoning: Potatoes need salt, but Gruyère is naturally salty. Taste a spoonful of the warm cream and adjust before pouring it over the potatoes.
• Rest before serving: That 10–15 minute rest is not optional; it dramatically improves texture and makes the gratin easier to serve cleanly.

Variations

• Herbed gratin: Add 1–2 teaspoons of finely chopped fresh thyme, rosemary, or a mix of soft herbs directly to the cream mixture before warming for an aromatic twist.
• Extra-cheesy blend: Replace 1/2 cup (50 g) of the Gruyère with finely grated Parmesan for a slightly sharper, nuttier flavor and an even crisper top.
• Garlic-forward version: Increase the minced garlic to 3 cloves and add a small pinch of garlic powder to the cream if you love a pronounced garlic note.

Storage & Make-Ahead

Let any leftover gratin cool to room temperature, then cover tightly and refrigerate for up to 3 days. To reheat a larger portion in the oven, cover the dish with foil and warm at 325°F (165°C) for 20–25 minutes, then uncover for the last 5–10 minutes to re-crisp the top. Individual portions can be reheated in the microwave at medium power until heated through, then briefly placed under a hot broiler to restore some of the surface browning if desired. For make-ahead, you can assemble the gratin up to the point of baking, cover tightly, and refrigerate for up to 24 hours. When ready to bake, let the dish sit at room temperature for 20–30 minutes while the oven preheats, then bake as directed, adding 5–10 minutes to the covered baking time if needed.

Nutrition (per serving)

Approximate values per serving (1/6 of the recipe): about 580 calories, 16 g protein, 44 g fat (27 g saturated), 32 g carbohydrates, 2 g fiber, and 650 mg sodium. Actual values will vary based on the specific brands of dairy and cheese you use and the exact size of your servings.