If you are looking for a comforting, cheesy, and indulgent side dish that always impresses, this Au Gratin Potatoes Recipe is exactly what you need. Layered with tender, thinly sliced russet potatoes, rich caramelized onions, and a luscious blend of gruyere and parmesan cheeses, this dish strikes the perfect balance between creamy and crispy. The subtle hints of thyme and garlic add an aromatic depth that makes each bite utterly irresistible. Whether it’s for a holiday feast, a family dinner, or just because you deserve a cozy treat, this Au Gratin Potatoes Recipe will quickly become your new favorite in the kitchen.
Ingredients You’ll Need
These ingredients are simple yet essential, coming together to provide the perfect harmony of flavor, creamy texture, and golden color that defines a classic Au Gratin Potatoes Recipe.
- 1 small yellow onion (finely diced): Adds natural sweetness and depth when caramelized, forming the flavorful base of the sauce.
- 3 tablespoons salted butter: Enhances richness and helps soften the onions to unlock their flavor.
- 4 cloves fresh garlic (minced): Brings a wonderful aromatic kick without overpowering the dish.
- 2 teaspoons fresh thyme leaves: Provides a subtle earthiness and herbal brightness to elevate the creamy sauce.
- 2 cups heavy cream: Key to the luscious, dreamy texture that makes this gratin so special.
- ½ cup milk: Lightens the cream slightly, helping to create the perfect consistency.
- 2 cups shredded gruyere cheese: Melts beautifully, offering a nutty, slightly sweet flavor characteristic of classic gratins.
- ½ cup grated Parmesan cheese: Adds sharpness and complexity to the cheesy sauce.
- ¼ teaspoon salt: Enhances every layer of flavor without making the dish salty.
- ¼ teaspoon pepper: Provides mild spiciness that balances the richness.
- 2 ½ lbs. russet potatoes: Their starchy quality makes them perfect for thin slicing and baking tender yet firm layers.
- Chives (to garnish): Adds a fresh pop of color and a mild onion flavor to finish the dish elegantly.
How to Make Au Gratin Potatoes Recipe
Step 1: Prepare Your Oven and Cream Mixture
Start by preheating your oven to 350°F to get it ready for baking. While you can do this a bit later, starting early sets the tone for a smooth cooking process. Then, mix your heavy cream and milk in a measuring cup and warm it in the microwave for a minute. This gentle tempering helps avoid curdling when added to the hot onions later, ensuring your sauce remains beautifully creamy.
Step 2: Caramelize the Onions
Next, melt your butter in a soup pot over medium heat and gently cook the diced onions until softened, which takes about 10 minutes. Lower the heat slightly and continue cooking for another 10 to 15 minutes until they develop a lovely golden caramel color. This slow process draws out the onion’s natural sweetness, creating a rich foundation for the dish. Then stir in the garlic and thyme and cook for 2 more minutes to release their fragrant flavors.
Step 3: Make the Cheese Sauce
Turn off the heat and let the pot cool briefly before gradually adding the warm cream and milk mixture. Then bring the liquid back to a boil over medium-high heat. Remove it from heat, and slowly add in the shredded gruyere and grated Parmesan cheese a little at a time, making sure it melts smoothly into the sauce. Lastly, sprinkle in your salt and pepper for seasoning. This cheesy sauce is what ties everything together, offering rich, gooey deliciousness in every bite.
Step 4: Slice the Potatoes Thinly
Using a sharp knife or preferably a mandoline slicer, cut the russet potatoes into uniform 1/8-inch thick slices. It is important not to go any thicker to ensure the potatoes cook evenly through the long bake without becoming mushy. Thin potato slices create tender layers that soak up the sauce perfectly.
Step 5: Layer the Potatoes and Sauce
Grease your baking dish lightly and arrange a third of the potato slices to cover the bottom in a single layer. Lightly sprinkle with salt for seasoning. Pour a third of the cheese sauce over the potatoes, spreading it evenly. Repeat this layering process two more times until all potatoes and sauce are used. This layering technique gives you those classic luscious pockets of creamy, cheesy potato goodness throughout.
Step 6: Bake and Brown
Cover your dish and bake for one hour, allowing the potatoes to cook through and the flavors to meld nicely. Afterward, remove the cover and bake uncovered for an additional 30 minutes, so the top develops a beautiful golden crust. If you want to take it a step further, broil the top on 425°F for 1 to 2 minutes to deepen the color and add a slight crispiness—but keep a close eye to avoid burning.
Step 7: Rest and Garnish
Once out of the oven, let the Au Gratin potatoes rest for 5 to 10 minutes. This step helps the sauce thicken and settle so it doesn’t run everywhere when served. Finally, sprinkle freshly chopped chives on top for a fresh, vibrant finish before digging in.
How to Serve Au Gratin Potatoes Recipe
Garnishes
Chopped fresh chives are an exceptional choice for garnishing an Au Gratin Potatoes Recipe because they lend a subtle onion flavor and a gorgeous pop of green color. You can also experiment with a sprinkle of crispy fried shallots or a dusting of smoked paprika if you’re feeling adventurous. These garnishes add complexity and texture contrast to the creamy dish.
Side Dishes
This Au Gratin Potatoes Recipe pairs beautifully with hearty mains. Think roasted chicken, tender steak, or succulent pork loin. It also complements roasted vegetables like Brussels sprouts or green beans for a balanced and delicious meal. The creamy potatoes bring richness that elevates any weekday meal or special occasion.
Creative Ways to Present
To impress your guests, try serving individual portions of the Au Gratin potates in small ramekins with a golden crust on top. Alternatively, bake it in a cast-iron skillet for rustic charm and serve straight from the pan. A delicate drizzle of truffle oil just before serving adds luxury, while a sprinkle of toasted breadcrumbs can introduce a crunchy texture to contrast the creamy layers.
Make Ahead and Storage
Storing Leftovers
Leftover Au Gratin potatoes should be stored in an airtight container in the refrigerator. They will stay fresh and delicious for up to 4 days. Keep in mind the sauce thickens as it chills, so you might want to add a splash of cream or milk when reheating to restore the creamy texture.
Freezing
Although freezing can slightly alter the texture, you can freeze this dish if necessary. Cool it completely, then cover tightly with plastic wrap and a layer of foil to prevent freezer burn. The Au Gratin Potatoes Recipe can be frozen for up to 2 months. Thaw thoroughly in the refrigerator before reheating to ensure even warming.
Reheating
Reheat leftovers gently in the oven at 325°F for 20 to 30 minutes, covering loosely with foil to avoid drying out. You can also reheat individual portions in the microwave, adding a splash of cream or milk to keep the sauce smooth and moist. Be sure to heat until warmed through but not boiling to maintain the perfect texture.
FAQs
Can I use other types of potatoes for the Au Gratin Potatoes Recipe?
Russet potatoes are ideal due to their starchy texture that bakes up tender. However, Yukon Golds work well too, offering a buttery flavor and creamy consistency. Avoid waxy potatoes like red or fingerlings as they won’t become as tender or absorb the sauce properly.
Do I need to peel the potatoes?
Peeling the potatoes is traditional and ensures a smoother texture, but if you prefer a bit more texture and rustic feel, you can leave the skin on as long as you wash them thoroughly. Keep in mind that skin-on potatoes may require slightly longer baking.
Why do I need to temper the cream and milk before adding?
Tempering warm cream with the hot onion mixture prevents the dairy from curdling or separating when combined. It helps keep your sauce silky and smooth rather than grainy, which is essential for the perfect Au Gratin potatoes.
Can I make this dish gluten-free?
Absolutely! This Au Gratin Potatoes Recipe contains no flour or gluten ingredients by default, making it naturally gluten-free. Just make sure any cheeses or other products you use are also gluten-free to be safe.
How can I make the top extra crispy without drying out the potatoes?
Broiling the dish uncovered for 1 to 2 minutes at the end of baking adds a beautiful golden crust. To prevent drying, watch the broil carefully and avoid overcooking. You can also sprinkle a small amount of breadcrumbs mixed with melted butter on top before baking to enhance crispiness.
Final Thoughts
This Au Gratin Potatoes Recipe is the kind of dish that feels like a warm hug on a plate. It’s rich, satisfying, and simple enough to make whenever you want to impress without fuss. So grab your potatoes and cheese, and give this recipe a try—you might just create a new family favorite that steals the spotlight at every meal.
Print
Au Gratin Potatoes Recipe
- Prep Time: 20 minutes
- Cook Time: 2 hours
- Total Time: 2 hours 20 minutes
- Yield: 12 servings
- Category: Side Dish
- Method: Baking
- Cuisine: French
- Diet: Vegetarian
Description
This classic Au Gratin Potatoes recipe features thinly sliced russet potatoes layered with a rich, creamy sauce made from caramelized onions, garlic, thyme, Gruyère, and Parmesan cheese. Baked to perfection with a golden, cheesy crust, this comforting dish is perfect for gatherings and pairs beautifully with a variety of mains.
Ingredients
Vegetables
- 1 small yellow onion (finely diced)
- 4 cloves fresh garlic (minced)
- 2 ½ lbs. russet potatoes (sliced 1/8-inch thick)
- Chives (to garnish)
Dairy
- 3 tablespoons salted butter
- 2 cups heavy cream
- ½ cup milk
- 2 cups shredded Gruyère cheese
- ½ cup grated Parmesan cheese
Herbs & Spices
- 2 teaspoons fresh thyme leaves
- ¼ teaspoon salt
- ¼ teaspoon pepper
Instructions
- Preheat the oven: Set your oven to 350°F (175°C) to allow it to reach the right temperature by the time the potatoes and sauce are ready for baking.
- Prepare cream mixture: Combine heavy cream and milk in a medium measuring cup with a spout. Microwave for 1 minute to warm the mixture, then set aside for later use.
- Caramelize onions: In a soup pot over medium heat, melt butter and add diced onions. Soften them for 10 minutes while stirring frequently, then reduce heat to medium-low and cook another 10-15 minutes until the onions start to brown and caramelize slightly.
- Add garlic and thyme: Stir in minced garlic and fresh thyme leaves, cooking for 2 additional minutes to release their fragrance.
- Combine cream and cheese sauce: Turn off the heat briefly to let the pot cool for 1 minute. Gradually stir in the warmed heavy cream and milk mixture. Increase heat to medium-high and bring to a boil. Remove from heat, then slowly add shredded Gruyère and grated Parmesan, allowing cheese to melt with each addition. Season with salt and pepper.
- Slice potatoes: Using a mandoline slicer or a knife, cut potatoes into 1/8-inch thick slices to ensure even cooking throughout the dish.
- Layer potatoes and sauce: Lightly grease a 2.5-quart or 9 x 13-inch baking dish. Arrange one-third of the potato slices on the bottom, lightly sprinkle with salt, then pour one-third of the cheese sauce over the layer. Repeat two more times to create three layers of potatoes and sauce.
- Bake covered: Cover the dish with foil or a lid and bake in the preheated oven for 1 hour, allowing the potatoes to cook fully and the sauce to meld.
- Finish baking uncovered: Remove cover and bake for an additional 30 minutes to develop a golden top. For extra color and crispness, optionally broil at 425°F for 1-2 minutes, watching carefully to prevent burning.
- Rest and garnish: Take the dish out of the oven and let it rest for 5-10 minutes so the sauce thickens and sets. Garnish with freshly chopped chives before serving.
Notes
- Use a mandoline slicer for uniformly thin potato slices, which ensures even cooking.
- Caramelizing the onions slowly adds a depth of flavor to the cheese sauce.
- For a crunchier top, broil carefully for 1-2 minutes at the end of baking.
- Letting the dish rest after baking helps the sauce thicken and improves slicing.
- This dish pairs wonderfully with roasted meats, salads, or as a hearty vegetarian main.
