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Rich, comforting, and surprisingly simple, these potatoes au gratin are an irresistible side dish that always gets rave reviews.
This classic potatoes au gratin recipe is one of my favorite Thanksgiving side dishes, and it’s also fitting for Christmas, a dinner party, or any meal that calls for something a little extra. It involves layering thinly sliced potatoes with heavy cream and grated cheese in a casserole dish, and then baking until the cream thickens and blankets the potatoes in a rich, creamy sauce. And while it’s certainly worthy of a special occasion, honestly, a pan of these potatoes makes any dinner feel like one.
“I only gave this five stars because I couldn’t give it 10 stars. This may be my favorite side dish ever. It is amazing!”
Potatoes Au Gratin vs Scalloped Potatoes
Potatoes au gratin and scalloped potatoes are similar dishes, but there are a few key differences. Both are made with thinly sliced potatoes baked until tender, but au gratin potatoes typically include cheese and are known for their rich, golden-brown top. Scalloped potatoes traditionally don’t contain cheese and are often flavored with onions and baked in a milk or cream sauce thickened with a roux.
What You’ll Need To Make Potatoes Au Gratin
- Russet Potatoes: With their high starch content, russets soak up the cream beautifully and bake into soft, melt-in-your-mouth layers. They’re the best choice for this dish. Skip the Yukon Golds here—they won’t give you the same texture.
- Heavy Cream: The secret to the luscious, velvety sauce. You might be tempted to swap in milk or half-and-half, but don’t—this recipe really needs heavy cream to thicken properly.
- Parmigiano Reggiano: Adds a salty, nutty depth that melts right into the potatoes, creating incredible flavor and texture. Be sure to use true Parmigiano Reggiano. If you can’t find it, Pecorino Romano makes a great substitute.
- Salt, Pepper & Thyme: These simple seasonings bring everything to life—the thyme is optional but adds a subtle earthiness that pairs perfectly with the creamy potatoes and cheese.
- Jump to the printable recipe for precise measurements
How To Make Potatoes Au Gratin
Slice the potatoes: Slice the potatoes as thinly and uniformly as possible so they cook at the same rate. A mandoline works well, but a sharp knife is all you need. If a potato feels wobbly, cut a thin slice lengthwise and place it cut-side down on the cutting board to create a stable base.
Season the potatoes: Toss the slices thoroughly with salt and pepper so the seasoning is evenly distributed. Potatoes need a generous amount of salt to bring out their flavor, so don’t be tempted to skimp.
Assemble the gratin: Arrange the potatoes in overlapping layers in a buttered baking dish, distributing the cheese and cream evenly as you go. Don’t worry about making the layers perfectly neat, but try to keep them fairly even so the potatoes cook uniformly. Be sure to pour in all of the cream—it will thicken as the gratin bakes, creating the rich, velvety sauce.
Bake until golden: Bake the gratin until the top is deeply golden and a knife slides easily through the potatoes with almost no resistance. Don’t cover the dish with foil; baking it uncovered is what gives you that beautiful browned top. Let it rest for a few minutes before serving so the cream can settle and thicken around the potatoes.
Finish with a sprinkle of fresh thyme and serve hot, while the top is crisp and golden and the potatoes underneath are creamy and tender.
Potatoes au gratin are best baked just before serving, but you can do some of the work ahead. See the recipe card below for my make-ahead, storage, and reheating instructions. If you love this recipe, try my cauliflower gratin or Brussels sprouts gratin next.
More Potato Side Dishes You May Like
Potatoes Au Gratin
Ingredients
- Butter to grease the baking dish
- 2½ lb Russet potatoes (3 to 4), peeled and very thinly sliced
- 1½ teaspoons salt
- ¼ teaspoon freshly ground black pepper
- 1 cup (4 oz) finely grated Parmigiano-Reggiano
- 2¼ cups heavy cream
- Fresh thyme, for serving (optional)
Instructions
- Preheat the oven to 350°F (175°C) and set an oven rack in the middle position. Grease an 8-in (20-cm) or 2-qt/2L baking dish with butter.
- In a large mixing bowl, toss the potatoes with the salt and pepper until evenly coated.
- Arrange some of the potato slices, edges overlapping, in a single layer on the bottom of the prepared baking dish. Sprinkle a quarter of the cheese over the potatoes, and then pour a quarter of the cream over the cheese. Repeat with the remaining potatoes, cheese, and cream, forming 4 layers. Pour any leftover cream over top.
- Place in the oven and bake, uncovered, for 60 to 75 minutes, or until the potatoes are tender when pierced with a knife and golden brown on top. Let the dish settle on the counter for about ten minutes. Sprinkle with fresh thyme, if using, and then serve.
Notes
Nutrition Information
This website is written and produced for informational purposes only. I am not a certified nutritionist and the nutritional data on this site has not been evaluated or approved by a nutritionist or the Food and Drug Administration. Nutritional information is offered as a courtesy and should not be construed as a guarantee. The data is calculated through an online nutritional calculator, Edamam.com. Although I do my best to provide accurate nutritional information, these figures should be considered estimates only. Varying factors such as product types or brands purchased, natural fluctuations in fresh produce, and the way ingredients are processed change the effective nutritional information in any given recipe. Furthermore, different online calculators provide different results depending on their own nutrition fact sources and algorithms. To obtain the most accurate nutritional information in a given recipe, you should calculate the nutritional information with the actual ingredients used in your recipe, using your preferred nutrition calculator.
Gluten-Free Adaptable Note
To the best of my knowledge, all of the ingredients used in this recipe are gluten-free or widely available in gluten-free versions. There is hidden gluten in many foods; if you’re following a gluten-free diet or cooking for someone with gluten allergies, always read the labels of your ingredients to verify that they are gluten-free.
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Jen: This is the one recipe of yours that did not turn out. I followed the recipe exactly and sadly – the cheese mixture curdled and the potatoes were al dente. The taste was fine it just looked un- appetizing. After researching WHY the curdling and al dente occurred – I now know that the high heat causes curdling and that making a cheese sauce will prevent it from happening again. Also, in the future before slicing I will par boil the potatoes. Thanks for all and please keep sharing – Renee
My brother, who is a fan of your recipes, made these potatoes for a Thanksgiving side and they were a hit. Outshined the turkey and my 2 homemade pies!
This is now my go to recipe for Au Gratin Potatoes! Soooo, easy and so much tastier than making the roux version, which I don’t really like. I add a bit of cheddar cheese along with the Parmesan. Sometimes I slice an onion very thin and incorporate it in but you really don’t have to. Love this one!
I’m planning to make this for a crowd of 25. How would you suggest I go about dividing it up? I’ll probably use those rectangular heavy duty foil looking disposable pans.
Hi Christy, I’d suggest multiplying the recipe times 4 and using four of the 8-inch square aluminum pans. Hope everyone enjoys!
Dear Jenn,
I made these last weekend and my husband couldn’t stop talking about them! He loves au gratin potatoes, and has always loved the recipe I usually use. I didn’t tell him that I was trying a new recipe. He raved that these were the best au gratin potatoes he had ever eaten. Thanks again for a fantastic recipe!
Katy
I made this recipe for our Thanksgiving dinner. It was a hit! I believe it was the most flavorful version of Au Gratin potatoes I have ever eaten! I used Parmigiano instead of Parmigiano-Reggiano–The only alteration I made.
This BY FAR is one of most delectible recipes I’ve ever found online! It is a regular in our household with a couple of minor changes–but its delicious as written.
I add gruyere cheese in each layer and to lessen the richness, use half and half versus full cream.
I soak the sliced potatoes in cold water for a few hours before prepping and then drain and dry them on paper towels. It seems to lessen the starch.
Best recipe ever!! Make it NOW! Leftovers are even better.
This was excellent! For the cheese, I had on hand packets of parm cheese from an italian restaurant and slices of american cheese. The secret to this being so good (and decadent) is the heavy cream!
I’d give this recipe more stars if possible because it has become one of our favorite from this site. It’s easy, satisfying, and needs no specialty ingredients to languish in the frig, never to be used again. It’s also amenable to some substitutions if necessary. It calls for Russet or Yukon Gold potatoes, but once I substituted one sweet potato for one of the Russets. No parmesan? Use Gruyere or Cheddar or a combo. Like onions or shallots, or even some garlic? Add some minced, scattered among the potatoes.
I have served this with roasted chicken, pork chops, ham (little pieces in with the potatoes), beef steaks. It really goes with any meat. It’s especially good with broccoli or brussels sprouts, as the strong tasting vegetable goes well with the creamy cheese sauce on the potatoes.
Try it. I bet you’ll agree with me that it is definitely a “keeper.”
This is the tastiest most comforting side dish you’ll ever make! I’ve made it more times than I can count…always have the ingredients on hand. It’s quick and easy to assemble. Sometimes I add a very thinly sliced sweet onion, so yummy!! Your family and guests will be impressed.