Why You’ll Love Roasted Garlic Potatoes au Gratin Recipe

The roasted garlic adds a deep, mellow flavor that transforms ordinary potatoes into something special
It’s a crowd‑pleaser — elegant enough for guests yet simple for weeknight meals
Layers of potatoes soak in creamy sauce and cheese, resulting in tender, flavorful bites
You can assemble ahead and bake when ready
Great variation potential — swap cheeses, herbs, or cream to suit your pantry

Ingredients

(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)

Potatoes, medium, starchy type
1 head of garlic
Heavy cream (double cream)
Whole milk
Unsalted butter
Fresh thyme leaves (or dried thyme)
Nutmeg
Grated Parmesan cheese (divided)
Shredded Gruyère or mozzarella cheese
Salt and pepper
Fresh chives (for garnish)

Directions

Preheat oven & roast the garlic
Preheat your oven to 375 °F (190 °C). Cut the top off the garlic head to expose the cloves, drizzle with olive oil, season with a pinch of salt, wrap in foil, and roast for about 30 minutes until soft and golden.
Prepare the baking dish and potatoes
Grease a 9×13‑inch (23×33 cm) baking dish. Peel the potatoes and slice them very thinly (a mandoline is helpful for uniform slices). Arrange the potato slices upright in layers in the baking dish until all are used.
Make the creamy sauce
In a saucepan over medium heat, combine heavy cream, milk, butter, half of the grated Parmesan, thyme, nutmeg, salt, and pepper. Heat gently until butter melts and ingredients are well combined (do not boil).
Incorporate roasted garlic
Once the garlic is cooled, squeeze the cloves out of their skins and mash into a paste. Stir this roasted garlic paste into the cream mixture.
Assemble and bake (covered)
Pour the creamy garlic mixture evenly over the layered potatoes, making sure all layers are coated. Cover the dish tightly with foil and bake for 40 minutes.
Finish uncovered
Remove the foil. Sprinkle the remaining Parmesan and the shredded cheese over the top. Return to the oven, uncovered, and bake for another 30 minutes or until the cheese is bubbly, golden, and potatoes are fork tender.
Rest & garnish
Let the gratin rest a few minutes before serving. Garnish with fresh chives.

Servings and timing

Yields: 8 servings Good Food Discoveries
Preparation time: about 30 minutes Good Food Discoveries
Baking time: 1 hour (40 min covered + 30 min uncovered) Good Food Discoveries
Total time: about 1 hour 40 minutes Good Food Discoveries

Variations

Use cheddar, Havarti, or Monterey Jack instead of (or along with) Gruyère
Use half cream and half milk (or lighter dairy) for a lighter version
Add layers of sliced onions or thinly sliced ham for extra flavor
Sprinkle breadcrumbs over the top in the last 10 minutes for extra crunch
Use fresh herbs like rosemary or parsley instead of thyme
Swap nutmeg for a pinch of smoked paprika for a twist

Storage/Reheating

Refrigerator: Store in an airtight container for up to 3 days. Good Food Discoveries
Freezing: The creator isn’t a big fan of freezing, but individual portions can be frozen for up to 2 weeks (texture may change). Good Food Discoveries
Reheating: Warm in the oven at low heat (about 325–350 °F / 160–175 °C) until heated through. Cover with foil if top browns too much.

FAQs

Which type of potatoes work best?

Starchy potatoes (like Russet or Maris Piper) are recommended because they absorb more liquid, helping to avoid a watery result.

Can I skip roasting the garlic and use raw garlic instead?

You can, but roasted garlic gives a sweeter, mellow depth — raw garlic may be sharper and more pungent.

Can I prepare this ahead of time?

Yes — you can assemble the dish (without the cheese topping) a day ahead, cover tightly, and refrigerate. Bake per instructions when ready.

Will the dish become too watery?

It can if potatoes are cut too thick, or if you use high‑water veggies. Uniform thin slices and using starchy potatoes help reduce excess liquid.

Can I substitute heavy cream with lighter milk?

Yes, you can use half‑and‑half or milk with melted butter, but the final dish may be less rich and creamy.

Can I omit nutmeg or thyme?

Yes — they add depth, but the dish will still be delicious without them or with alternate herbs.

What if the top browns too fast?

If the cheese browns too quickly, you can loosely cover with foil in the final minutes.

Can I add other ingredients like vegetables or meat?

Yes — thinly sliced onions, ham, bacon bits, or mushrooms can be layered for extra flavor.

Is it possible to make smaller or larger batches?

Absolutely — adjust quantities according to your dish size, keeping ratios of cream, cheese, and potatoes consistent.

How should I serve this gratin?

Serve warm as a side with roasted meats, grilled vegetables, or as part of a holiday meal.

Conclusion

Roasted Garlic Potatoes au Gratin is a comforting, flavorful side dish that elevates simple potatoes with creamy sauce, melted cheese, and the mellow sweetness of roasted garlic. It’s flexible, forgiving, and perfect for gatherings or cozy dinners. Try it once — it’s likely to become a favorite.