This delicious potatoes au gratin recipe is easy to make during the holidays. It’s the perfect cheesy potato side dish that complements any meal.
Recipe Science
- Choose waxy Yukon gold potatoes. The flesh is buttery and holds its shape well when scooped and served, preserving the layers.
- Gruyere melts smoothly with a nutty flavor, while sharp cheddar provides bold, aged notes. They enhance the bechamel’s creaminess and create a golden, gooey crust.
- A roux prevents the milk from curdling by stabilizing the sauce during baking and adds creaminess for better texture.
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Featured Comment 45
“Hands down, BEST Au Gratin Recipe ever!! I’ve been cooking for 50 years and thought I made the best, but I stand corrected!! YOURS are the best!! Thank you for my new recipe! We’ve dubbed them Holiday Potatoes.”—Jeannie
Why It Works
Creamy, cheesy potatoes au gratin are a classic, crowd-pleasing side dish that’s easy to make—unless the cream curdles or the potatoes don’t turn out fork-tender. With the right tips, I’ll show you how to avoid these common issues for perfect results.
This potato au gratin recipe uses multiple layers of thinly sliced Yukon gold potatoes topped with a roux-based sauce to stabilize the milk in the dish. Aged sharp cheddar and buttery gruyere cheese are mixed in the sauce and sprinkled on the potatoes. It’s a comforting dish that can be prepared ahead of time and enjoyed later.
Ingredients You’ll Need
- Potatoes: For au gratin, choose a medium-sized waxy type of potato like Yukon gold potatoes. Once cooked, the flesh has a buttery texture and holds its shape well when scooping out each serving.
- Cheese: The best cheese combination for the au gratin potatoes is gruyere and sharp cheddar cheese. Gruyere is a medium-hard cheese with a nutty taste and a hint of sweetness. It has excellent melting properties, and I always use it when making French onion soup. Sharp cheddar has a stronger aged flavor and a semi-hard texture. Together they melt effortlessly in the bechamel sauce and create a nice gooey, browned crust on top of the potatoes.
- Alliums: Minced garlic and chopped yellow onions are sauteed in butter to build a savory and earthy base for the cream sauce.
- Cream Sauce: The basic technique for creating a milk sauce is using a thickening agent, like a roux. This recipe uses equal parts by volume of butter and flour, which cooks into a paste. Then, gradually incorporate milk while simmering until the thickness coats a spoon. It’s seasoned with salt, black pepper, and nutmeg.
- Herbs: Chives garnish the potato side dish and add a delicate onion flavor.
See the recipe card below for all ingredients and measurements (US and metric).
Ingredient Substitutions
This au gratin potatoes recipe is easy to customize! Try these tasty options:
- Potato Substitutes: Russets are my second choice because their delicate texture tends to absorb the sauce and become too creamy. I prefer to use Russet potatoes for mashed potatoes instead. Red potatoes can also be used for a waxy texture.
- Make the Sauce Creamier: You can use heavy cream for a richer consistency.
- Cheese Swaps: Use shredded cheeses that melt well, like Swiss cheese, gouda, or mozzarella. Add some parmesan cheese for a nutty flavor.
- Herbs: Garnish with fresh herbs like chopped parsley, thyme, rosemary, tarragon, or green onions.
- Add Meat: Sprinkle on smoky roasted bacon, pancetta, or make scalloped potatoes with ham.
How to Make Au Gratin Potatoes
Step 1: Preheat the Oven
Position your oven rack in the center to ensure even baking, then preheat to 400ºF (200ºC). This temperature allows the potatoes to cook through while developing a beautifully golden brown, bubbly top.
Step 2: Make the Cream Sauce
Melt butter in a skillet over medium-low heat, then sauté garlic and onions until fragrant, about 2 minutes. Stir in flour and cook for 2 minutes.
Gradually whisk in the milk, cooking until thickened, 2 to 3 minutes. Turn off the heat and season with salt, pepper, and nutmeg. This creates a smooth, flavorful sauce for your potatoes.
Ingredient Chemistry: If you only add milk to the potatoes, the proteins are at risk of curdling over time. Once the protein hits a temperature of 180ºF (82ºC) and above, they begin clumping together. Considering the potatoes are cooked at 400ºF (204ºC) for nearly an hour to tenderize, it’s best to build a little safety cushion with a roux. The creamy texture added to the sauce is just a tasty bonus!
Step 3: Add the Cheese
Stir in Gruyere and sharp cheddar cheese until melted and combined, creating a rich, cheesy bechamel sauce. This technique is also used in macaroni and cheese, but we use potatoes instead of pasta. If made correctly, the sauce should spread easily between the potato layers instead of pooling at the bottom of the baking dish.
Step 4: Assemble the Casserole
In a greased 8-inch square baking dish, layer half the potatoes, overlapping them.
Spread half of the cheese sauce and shredded cheese. Repeat the layering once more time with the remaining ingredients.
Step 5: Bake
Cover the dish with foil and bake in a preheated oven at 400ºF (200ºC). This traps the heat to steam and softens the spuds. After 30 minutes, remove the foil so that the cheese layer browns. Cook for about 20 to 25 minutes or until the potatoes are tender.
Step 6: To Serve
Allow the casserole to cool on a wire rack for 10 to 15 minutes before serving. This helps the layers set. Garnish the potatoes with fresh chives. This side dish is delicious with roast turkey for Thanksgiving or roasted chicken any day of the week.
Frequently Asked Questions
In French cooking, “gratin” refers to a dish topped with breadcrumbs, cheese, or both and baked until it forms a golden, crispy crust. The word “gratin” comes from the French term “gratter,” meaning “to scrape,” which traditionally refers to scraping off the crispy top layer. This technique is used to add both texture and flavor to dishes like potatoes au gratin.
Scalloped potatoes are traditionally cut into thicker rounds, about ¼-inch, layered, and baked in a casserole dish. Cream, milk (or both), and aromatics like garlic, onions, and herbs are added. On the other hand, Au gratin has thinly sliced potatoes, ⅛-inch thick potato slices, and cheese added to the recipe. You might see breadcrumbs sprinkled on top for extra crunch. The culinary terms are often used interchangeably, which causes a bit of confusion.
To make creamy au gratin potatoes, start by creating a roux-based sauce. The flour in the roux helps stabilize the cream sauce by thickening it as it bakes. The starches in the flour hold onto the water in the milk, preventing the oils and fats from separating, which keeps the sauce smooth and creamy. As the starches heat up, they swell, creating a rich, velvety texture that perfectly coats the potatoes.
This side dish can be assembled two days ahead, covered, and refrigerated until ready to bake. Bake time may need to be slightly increased as the pan and ingredients will be cold.
Serve This With
If you tried this Potatoes Au Gratin Recipe, please leave a 🌟 star rating and let me know how it went in the 📝 comments below!
Potatoes Au Gratin
Ingredients
- ¼ cup unsalted butter
- 1 tablespoon minced garlic
- ½ cup finely chopped yellow onion
- ¼ cup all-purpose flour
- 2 cups whole milk
- ¾ teaspoon kosher salt
- ½ teaspoon black pepper
- ⅛ teaspoon nutmeg
- 2 pounds yukon gold potatoes, peeled, cut into ⅛" thick slices
- 1 cup shredded gruyere cheese
- 1 cup shredded sharp cheddar cheese
- 2 teaspoon chopped chives
Instructions
- Preheat the Oven – Set the oven rack to the middle position. Heat to 400ºF (200ºC).
- Make the Cream Sauce – Melt the butter in a large skillet over medium-low heat. Add garlic and onions, and saute until fragrant, 2 minutes. Add flour, whisk to combine, stir and cook for 2 minutes. Gradually whisk in milk and cook until thickened over medium heat, 2 to 3 minutes. Turn off the heat and whisk in salt, pepper, and nutmeg.
- Add the Cheeses – Add ½ cup gruyere and ½ cup sharp cheddar cheese, and stir to combine.
- Assemble the Casserole – Grease the bottom and sides of an 8-inch square casserole dish. Layer half of the potatoes in overlapping rows in the dish. Spread half of the cheese sauce over the potatoes. Sprinkle ¼ cup gruyere and ¼ cup cheddar over the sauce. Layer the remaining potatoes, followed by the cheese sauce, and sprinkle with the remaining gruyere and cheddar cheese.
- Bake – Cover with foil and place on a baking sheet. Bake for 30 minutes. Remove the foil and continue baking until the potatoes are tender and the cheese is browned and bubbly, 20 to 25 minutes.
- To Serve – Transfer the casserole to cool on a wire rack for 10 to 15 minutes before serving. Garnish potatoes with chives.
Notes
- Make Ahead: Assemble, cover, and refrigerate for 2 days before baking. More baking time may be needed as the ingredients and pan will be cold.
- Storing: Store in an airtight container in the refrigerator for up to 5 days. Freeze for up to 1 month.
- Reheating: Cover and reheat a small portion in the microwave on a high setting in 15 to 30-second increments until hot. Alternatively, cover and reheat in the oven at 350ºF (177ºC) until hot.
Nutrition Facts
Percent Daily Values are based on a 2000-calorie diet. All nutritional information is based on estimated third-party calculations. Each recipe and nutritional value will vary depending on the brands you use, measuring methods, and portion sizes per household.
Maria T. says
Had this last with BBQ steak and salad. Absolutely delicious. I used the recommended Gruyere and sharp Cheddar for their great flavor and Yukon Gold for their texture. Not so time consuming with a mandolin. Always very careful. I made this dish earlier in the day, which worked out perfectly.
Jessica Gavin says
Wow, the steak and potatoes combination sounds lovely! I’m glad that you found this potato recipe easy to prepare. Bravo Maria!
Laura says
Omg, this is fantastic! I followed the recipe exactly with only a pan shape differentiation (I had round and tall, not square) which resulted in a longer bake time. But the flavor! Wow. Just wow. Thank you for this awesome recipe!
Jessica Gavin says
Whoo-hoo! Thrilled to hear that you enjoyed the potato recipe.
AQ says
Hi Jessica
Can I prep and freeze this casserole a few weeks ahead of thanksgiving and thaw it the night before and freeze day of or bake frozen the day of?
Pl lmk
Thanks in advance.
Jessica Gavin says
Yes, you can prep, freeze, then defrost the casserole in the refrigerator the night before. You could bake from frozen, but it will take a lot longer to account for defrosting the ingredients in the oven.
Shandi says
Hi Jessica, is it possible to completely assemble this dish, cover tightly and freeze it. Then bake it frozen the day of? Or should I make it, bake it, then freeze it and re-heat the day of? I’m just trying to do as much ahead of Thanksgiving as possible. Thanks for your help!
Jessica Gavin says
If you are baking the casserole within 2 days, I would cover it tightly then refrigerate it, they bake the day of. Let me know how it goes!