Roasted Garlic Potatoes Au Gratin

Creamy, cheesy layers of thinly sliced potatoes infused with roasted garlic and herbs.

Introduction

Potatoes Au Gratin is a comfort food classic that’s made its way into the hearts of families around the globe. While traditional versions are rich and delicious on their own, this variation—Roasted Garlic Potatoes Au Gratin—elevates the dish to an entirely new level with the mellow sweetness of roasted garlic, herbaceous thyme, and a golden crust of gooey melted cheese.

Perfect for Sunday dinners, holidays, or potlucks, this dish delivers both rustic charm and gourmet satisfaction. Whether you’re preparing it as a show-stopping side or the centerpiece of a cozy vegetarian meal, this version will leave everyone asking for seconds.

In this comprehensive article, we’ll walk through everything you need to master this recipe: from choosing the right type of potatoes and properly roasting garlic to assembling, baking, and customizing the dish. You’ll also find expert tips, variations, and nutritional insights.

 Ingredients (US Measurements)

To serve 8 people:

• 8–9 medium starchy potatoes (about 2.6 lbs), thinly sliced (Yukon Gold or Russets work best)

• 1 head garlic, top sliced off for roasting

• 1 tablespoon olive oil (for roasting the garlic)

• 1 cup heavy cream

• ¼ cup whole milk

• 1 tablespoon unsalted butter, plus extra for greasing the baking dish

• 1 teaspoon fresh thyme leaves (or ⅓ teaspoon dried thyme)

• ¼ teaspoon ground nutmeg

• ½ cup grated Parmesan cheese, divided

• 2 cups shredded Gruyère or mozzarella cheese

• Salt and pepper, to taste

• Fresh chives, chopped for garnish

 Preparation Time

• Prep Time: 15 minutes

• Cook Time: 1 hour 10 minutes

• Total Time: 1 hour 25 minutes

• Servings: 8

• Calories: ~395 kcal per serving

 Instructions: How to Prepare Roasted Garlic Potatoes Au Gratin

 Step 1: Roast the Garlic

Roasted garlic is the hero ingredient of this recipe—it’s what gives the dish its distinct, sweet-savory depth.

Instructions:

• Preheat your oven to 375°F (190°C).

• Slice the top off a head of garlic to expose the cloves.

• Drizzle 1 tablespoon olive oil over the exposed cloves.

• Sprinkle with a pinch of salt.

• Wrap the garlic head in foil.

• Roast for 30 minutes, until soft and golden.

• Let it cool, then gently squeeze the garlic cloves out of their skins and mash them into a paste. Set aside.

Why This Matters:
Roasting mellows the garlic’s sharpness and enhances its sweetness. This depth of flavor permeates the entire gratin.

 Step 2: Prepare the Potatoes

• Peel and thinly slice the potatoes (around ⅛-inch thick). A mandoline slicer ensures even slices, which is key to even cooking.

• Place the slices in a bowl of cold water as you work to prevent browning and to rinse off excess starch.

Note: Dry the slices with paper towels before layering to prevent excess liquid in the dish.

 Step 3: Prepare the Cream Sauce

In a small saucepan:

• Combine:

  • 1 cup heavy cream

  • ¼ cup whole milk

  • 1 tbsp butter

  • ½ of the grated Parmesan (¼ cup)

  • Thyme, nutmeg, salt, and pepper to taste

• Gently warm over medium-low heat, stirring occasionally.

Once warm and the cheese is mostly melted:

• Stir in the mashed roasted garlic paste.

• Whisk until smooth and fully combined. Do not let it boil.

Result: A luxurious, infused cream base that ties the entire dish together.

 Step 4: Assemble the Dish

• Grease a 9×13-inch baking dish with butter.

• Drain and pat the potato slices dry.

• Layer them vertically or slightly shingled across the dish for a pretty presentation and even baking.

• Pour the garlic cream mixture evenly over the potatoes, letting it seep into the cracks.

• Cover tightly with foil.

 Step 5: Bake in Stages

Stage 1: Covered Baking

• Place the foil-covered dish into the preheated oven.

• Bake for 40 minutes until potatoes start to become tender.

Stage 2: Uncover and Add Cheese

• Remove foil.

• Sprinkle the remaining ¼ cup Parmesan and the full 2 cups of shredded Gruyère or mozzarella on top.

• Return to oven and bake uncovered for 30 minutes, until golden brown and bubbly.

 Step 6: Let It Rest

• Remove from oven and let sit for at least 10 minutes before serving.

• This helps the sauce thicken and flavors meld.

 Step 7: Garnish and Serve

• Garnish with chopped fresh chives.

• Slice and serve warm as a side dish or vegetarian main.

 Expert Tips for Success

1. Potato Choice:
   Use starchy potatoes like Yukon Gold or Russet for that tender-yet-structured texture.

2. Uniform Slicing:
   A mandoline ensures each slice cooks at the same rate.

3. Roasting Garlic Ahead:
   You can roast the garlic up to 3 days in advance and refrigerate it.

4. Letting It Rest:
   Crucial! This allows the sauce to thicken and prevents runny servings.

5. Customize Your Cheese:
   Don’t be afraid to swap Gruyère with cheddar, fontina, or even blue cheese for different flavor profiles.

6. Make Ahead:
   This dish holds up beautifully in the fridge. Assemble ahead and bake the next day, or reheat gently at 350°F for 20 minutes.

 Variations

• Add Protein: Mix in diced ham or cooked bacon between layers.

• Low-Carb Version: Substitute half the potatoes with thin-sliced turnips or cauliflower.

• Herb Upgrade: Try rosemary, sage, or tarragon for seasonal flavor changes.

• Spicy Twist: Add a dash of cayenne or chili flakes to the cream mixture for some heat.

 Storage & Reheating

• Refrigerate: Store leftovers in an airtight container for up to 3 days.

• Freeze: Wrap tightly in foil and freeze for up to 2 months. Thaw overnight before reheating.

• Reheat: Use the oven or toaster oven at 350°F for 15–20 minutes until heated through.

 Wine Pairing Suggestions

• White: A creamy Chardonnay or crisp Sauvignon Blanc.

• Red: A light-bodied Pinot Noir complements the earthy potatoes and garlic.

• Non-Alcoholic: Try a rosemary-infused lemonade or sparkling water with lemon and thyme.

 Nutritional Breakdown (per serving)

 Why You’ll Love This Recipe

• Comforting and Elegant: It’s the kind of dish that feels rustic but tastes like fine dining.

• Flavorful Layers: Roasted garlic + cream + cheese = unbeatable.

• Crowd-Pleaser: Ideal for family gatherings, dinner parties, and special occasions.

• Make-Ahead Friendly: Saves you time without compromising flavor.

Final Thoughts

Roasted Garlic Potatoes Au Gratin is more than just a side dish—it’s a celebration of texture, flavor, and comfort. Whether you’re preparing it for a holiday feast or just a cozy night in, this recipe delivers both warmth and wow factor.

From the rich roasted garlic notes to the bubbling cheese crust, every bite tells a story of homemade indulgence and culinary care. Try it once, and it’ll likely become a repeat favorite in your kitchen repertoire.