Why You’ll Love Roasted Garlic Potatoes au Gratin Recipe
This dish feels special enough for holidays but is simple enough for a cozy family dinner. Roasting the garlic first gives the sauce a mellow, sweet flavor that blends beautifully with the cream, thyme, nutmeg, and cheese. The potatoes turn tender inside while the top becomes bubbly, golden, and irresistible.
Ingredients
(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)
8-9 medium starchy potatoes, about 1.2kg, thinly sliced
1 large head garlic, top cut off
1 cup heavy cream or double cream
1/4 cup whole milk
1 tablespoon unsalted butter, plus more for greasing
1 teaspoon fresh thyme leaves, or 1/3 teaspoon dried thyme
1/4 teaspoon nutmeg
1/2 cup grated parmesan cheese, divided
2 cups shredded Gruyère or mozzarella cheese
Salt and pepper, to taste
Fresh chives, for garnish
Directions
Preheat the oven to 375°F (190°C).
Cut the top off the garlic head to expose the cloves. Place it on foil, drizzle with olive oil, season with a pinch of salt, wrap tightly, and roast for about 30 minutes, until soft and golden. Let it cool slightly.
Grease a 9×13-inch baking dish with butter.
Peel and thinly slice the potatoes. A mandoline helps create even slices.
Arrange the potato slices upright in layers in the prepared baking dish until all potatoes are used.
In a saucepan, combine the heavy cream, milk, butter, half of the parmesan, thyme, nutmeg, salt, and pepper. Warm over medium heat until the butter melts and the mixture is smooth. Do not boil.
Squeeze the roasted garlic cloves from their skins and mash into a paste. Stir the garlic paste into the cream mixture.
Pour the cream mixture evenly over the potatoes. Cover the dish tightly with foil.
Bake for 1 hour and 15 minutes.
Remove the foil and sprinkle the top with Gruyère or mozzarella and the remaining parmesan.
Bake uncovered for another 15 minutes, or until the cheese is bubbly and golden and the potatoes are fork-tender.
Let the dish rest for a few minutes before serving. Garnish with fresh chives.
Servings and timing
Servings: 8
Prep time: 30 minutes
Cook time: 2 hours
Total time: 2 hours 30 minutes
Variations
Use Gruyère for a nutty, classic flavor or mozzarella for a milder, extra-melty finish.
Add crispy bacon pieces between the potato layers for a smoky twist.
Swap thyme for rosemary for a stronger herb flavor.
Add caramelized onions for extra sweetness and depth.
Use a mix of parmesan and sharp cheddar for a richer cheese flavor.
Storage/Reheating
Store leftovers in an airtight container in the refrigerator for up to 4 days.
To reheat, cover with foil and warm in a 350°F (175°C) oven until heated through. Remove the foil for the last few minutes if you want the top to crisp again.
You can also reheat individual portions in the microwave, though the topping will be softer.
Freezing is possible, but the creamy sauce may change texture slightly after thawing.
FAQs
Can I make Roasted Garlic Potatoes au Gratin ahead of time?
Yes. You can assemble the dish a few hours ahead, cover it tightly, and refrigerate it. Bake when ready, adding a little extra time if it goes into the oven cold.
What potatoes work best for au gratin?
Starchy potatoes work best because they become tender and creamy as they bake. Russet potatoes or similar varieties are a great choice.
Can I use mozzarella instead of Gruyère?
Yes. Mozzarella gives a mild, creamy, stretchy topping. Gruyère gives a more classic, nutty flavor.
Do I have to roast the garlic first?
Roasting the garlic is highly recommended because it makes the flavor sweeter and softer. Raw garlic would taste much sharper.
Can I slice the potatoes by hand?
Yes, but try to slice them as evenly and thinly as possible so they cook at the same rate.
Why are my potatoes still firm?
They may have been sliced too thick, packed too tightly, or need more baking time. Cover the dish again and continue baking until fork-tender.
Can I use half-and-half instead of heavy cream?
Yes, but the sauce will be lighter and slightly less rich.
How do I keep the top from browning too fast?
Cover the dish loosely with foil if the cheese browns before the potatoes are fully tender.
Can I add more cheese?
Yes. You can add extra cheese on top or between the layers, but too much may make the dish heavier and oilier.
What should I serve with this dish?
It pairs well with roast chicken, steak, turkey, baked fish, or a fresh green salad.
Conclusion
Roasted Garlic Potatoes au Gratin is a rich, comforting side dish with tender layers of potatoes, creamy roasted garlic sauce, and a golden cheesy topping. It is simple, elegant, and perfect for both holiday meals and cozy dinners.
