Au Gratin Potatoes are thinly sliced golden potatoes layered in a rich, creamy, and cheesy sauce. This tasty side dish is always a hit!
Need more oven space? Try my Crockpot Au Gratin Potatoes instead!
My Favorite Potatoes Au Gratin Recipe
The best au gratin potatoes are creamy, cheesy, and full of rich flavor—and this recipe has it all!
Here’s a quick overview:
- Buttery Yukon gold potatoes
- Three kinds of cheese for the best possible flavor
- A creamy, cheesy sauce
- Fresh thyme for a restaurant-quality flavor
Once you try these from-scratch potatoes, you’ll never want to go back to the boxed mix.
Ingredients
- Gold potatoes: Yukon golds are best for their buttery flavor and creamy texture.
- Butter: Unsalted is best for controlling salt.
- Garlic: Fresh minced gives the most flavor; jarred works too.
- Flour: Thickens the sauce nicely.
- Milk: Whole milk makes the sauce rich and creamy. Skip skim or plant-based options.
- Cheddar cheese: Grate your own cheese or the best melt!
- Gruyère cheese: The secret to the best Au Gratin! Creamy with a nutty flavor.
- Parmesan: Fresh grated melts best and has great flavor.
- Thyme: Fresh herbs add flavor, but dried works too. Don’t like thyme? Skip it!
How To Make Au Gratin Potatoes
- Preheat oven: Set to 350°F and grease a 9×9-inch baking dish.
- Slice potatoes: Peel and slice thinly.
- Make sauce: Melt butter, cook garlic, whisk in flour, then add milk. Boil, thicken, and stir in Cheddar.
- Layer potatoes: Layer potatoes, Gruyère, and thyme in the pan.
- Bake: Cover with foil, bake for 1 hour 15 minutes, then check tenderness.
- Add Parmesan and bake: Sprinkle Parmesan, bake uncovered 10–15 minutes. Let rest before serving.
Quick Tip
These prep tools make the time fly!
- Sharp peeler
- Mandoline slicer
Set the Mandoline slicer to 1/8-inch thickness to get 6 cups of potatoes.
How To Make Ahead Of Time
Assemble and bake. Let cool with foil on, then add cheese, cover with plastic wrap, and refrigerate.
To serve, let sit at room temp for 1 hour. Cover with foil and bake at 350°F for 20–30 minutes. Uncover and bake another 10–15 minutes, until golden and bubbly.
What To Serve With Au Gratin Potatoes:
- For holidays, pair with Crockpot Turkey Breast, Sweet Potato Casserole, Thanksgiving Salad, and no-knead Dinner Rolls.
- For Easter, serve with Deviled Eggs, Asparagus Salad, Roasted Vegetables, and Drop Biscuits.
- For everyday dinners, enjoy with Blackened Chicken, Turkey Meatloaf, or Lemon Parmesan Chicken.
More Potato Recipes To Love:
- Cheesy Potatoes with a breadcrumb topping
- Roasted Potatoes with a simple seasoning
- Creamed Potatoes my mother-in-law’s famous recipe!
- Smashed Potatoes with paprika and garlic powder
- Mashed Potatoes with butter and cream
Au Gratin Potatoes
Au Gratin Potatoes start with thin slices of golden potatoes, layered in a rich, creamy, and ultra-cheesy sauce. This savory side dish is a comfort food guaranteed to be a crowd-pleaser!
Equipment
- 9 x 9-inch baking pan
- Large pot nonstick
Ingredients
- Cooking spray
- 6 packed cups baby gold potatoes 2 pounds, see note 1
- 3 tablespoons unsalted butter
- 2 teaspoons minced garlic 2 cloves
- 3 tablespoons flour
- Salt and pepper
- 2 cups milk see note 2
- 1 cup shredded sharp Cheddar cheese 3 ounces
- 1 cup shredded Gruyère cheese or more Cheddar, 3 ounces, divided
- 1/2 cup freshly grated Parmesan cheese see note 3
- 2 teaspoons fresh thyme or 1/4 teaspoon dried, optional
Instructions
- Preheat oven to 350°F. Grease a 9×9-inch (or 2-quart) baking pan with cooking spray and set aside.
- Peel and thinly slice potatoes (1/8-inch thick). I use a mandolin slicer for speed and accuracy (see note 1). Measure 6 tightly packed cups of sliced potatoes.
- In a large nonstick pot, melt butter over low heat. Add garlic and sauté for 1 minute until fragrant. Stir in flour and whisk constantly for 1 minute until smooth (avoid browning). Gradually whisk in 1 cup of milk until smooth. Increase heat to medium-high and gradually add the second cup of milk. Stir occasionally until the mixture boils. Season with salt and pepper (I use 1 teaspoon salt and 1/4 teaspoon pepper).
- Once boiling, reduce heat to medium-low and stir constantly for 2 minutes until the sauce thickens (see note 4). Remove from heat and let cool for 2 minutes. Stir in Cheddar cheese, a handful at a time, until melted and smooth. Add the sliced potatoes and stir to coat.
- Assemble the dish by layering 1/3 of the potatoes in the prepared pan, then sprinkle in 1/2 cup Gruyere cheese and 1/3 of the fresh thyme. In the same pan, repeat with another 1/3 of the potatoes, the remaining 1/2 cup Gruyere, and 1/3 thyme. Finish with the remaining potatoes and thyme.
- Cover the pan with foil and bake for 1 hour 15 minutes. Remove the foil and check for tenderness by piercing the potatoes with a knife. If not tender, bake a few more minutes and check again. Once tender, sprinkle 1/2 cup Parmesan cheese on top.
- Bake uncovered for another 10–15 minutes or until golden and bubbly. For extra color, broil for 1 minute at the end. Let stand for 5–10 minutes before serving to allow the sauce to thicken.
Video
Recipe Notes
Note 1: Yukon gold potatoes are my favorite, but russet potatoes also work. Peel potatoes, rinse in cool water, then use a mandoline slicer set at 1/8th-inch thickness to cut potatoes.
Note 2: Whole milk works best for the richest result. 2% or 1% milk work, but avoid skim or plant-based milk alternatives.
Note 3: Grab a block of Parmesan cheese and grate on the small holes of a grater. Alternatively, use finely grated Parmesan cheese. Do not use shelf-stable Parmesan.
Note 4: The sauce should coat the back of a wooden spoon. If you can trace a clear line across the back of the spoon with your fingertip, and it stays, the sauce is thick enough.
Nutrition
Serving: 1serving | Calories: 484kcal | Carbohydrates: 38g | Protein: 23g | Fat: 27g | Saturated Fat: 16g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 6g | Trans Fat: 0.2g | Cholesterol: 80mg | Sodium: 383mg | Potassium: 897mg | Fiber: 4g | Sugar: 4g | Vitamin A: 836IU | Vitamin C: 36mg | Calcium: 647mg | Iron: 2mg
Nutrition information is automatically calculated, so should only be used as an approximation.
As Chelsea’s sister and employee I have made and LOVED this recipe! They are always a hit!
Hi, I have three questions. 1) If I wanted to add onions to this recipe how would I go about doing that? Should I sauté them in butter before I add the garlic? Do I need to add more butter to the recipe in order to do that or should I stick to the amount of butter that is called in the recipe) 2) Does making this dish ahead of time, putting it in the fridge and then reheating it the next day change the texture or taste of the dish vs making it and serving it the same day? Which way is better? And then 3) if I needed to triple this recipe should I make it all together in the same dish or use separate dishes? Will this change the time it takes to cook? I’m so excited to try this recipe, it looks amazing! I’m sorry for all the questions! I have little to no experience cooking and this is my first time cooking for 22 people and I’m a little nervous lol any help is much appreciated 🙂
Hi! I’m so glad you’re making this—what a great dish for a crowd! And your questions are totally valid. Here’s the breakdown:
1) Adding onions
Yes, you can! Dice 1 small yellow onion and sauté it with the butter over low heat until soft (about 6–8 minutes), then add the garlic and continue the recipe. No need to add extra butter—the 3 tablespoons is enough.
2) Making ahead vs. fresh
This dish is best fresh—creamy sauce, crispy top. But you can make it ahead and reheat:
Cool, cover, and refrigerate.
Reheat covered at 350°F for 25–30 minutes, then uncover to crisp the top.
Even better: assemble it ahead and bake fresh the day of for the best texture.
3) Tripling the recipe
For 22 people, triple the recipe but use 3 separate 9×9 pans (or 2-quart equivalents). Don’t combine in one large dish—it won’t cook evenly.
Bake all at once, rotating halfway through. Time should be about the same—just check for tenderness before uncovering.
You’ve got this! So excited for you to try it—let me know if you have any other questions!
I am going to make these potatoes for Thanksgiving dinner. A bit confused on directions. It read layer 1/3 of potatoes with 1/2 cup of guyre cheese and then repeat. If you 2x’s recipe it call for 2 cups of cheese. So I assume I add 1 cup of cheese on each layer. I hope you see this and have time to respond. Thanks. By the way all your recipes are the very best.
Our family really loves potatoes with the skins on. Do you think this would be a problem? Can’t wait to try your recipe for the upcoming holidays!
With gold potatoes I don’t see this being a problem! 🙂 Enjoy I hope you love whatever you try!
Thanks SO much for responding – we’ve always loved your recipes, and can’t wait to try this one soon! Xoxo B
Question: I see instructions for make ahead and refrigerate…do you think it’d work to make ahead, cover the same way and freeze, then thaw before baking? They look amazing, Chelsea!
Honestly I’m not sure! I’m so sorry Cathy! I’ve never tried freezing this recipe!