Scalloped Potatoes Au Gratin Recipe

If you’re looking for a rich, cozy, crowd-pleasing side, this Scalloped Potatoes Au Gratin Recipe is the one I come back to again and again—layers of tender potatoes, a velvety cheese sauce, and that irresistible golden brown top.

A creamy, cheesy classic that always feels special

There’s something about scalloped potatoes au gratin that makes a dinner table feel a little more welcoming. Maybe it’s the bubbling edges. Maybe it’s the way that creamy cheese sauce settles into every layer of potato. Or maybe it’s because this dish shows up when we really want to feed people well—holidays, Sunday suppers, potlucks, and those chilly nights when everyone wants comfort food and seconds.

This Scalloped Potatoes Au Gratin Recipe sits right in that sweet spot between everyday practical and company-worthy. It’s a classic potato au gratin with thinly sliced potatoes baked in a rich cream sauce, then topped and finished until beautifully browned. The result is everything you want from cheesy scalloped potatoes: soft centers, a silky texture, and that deeply savory, cheesy finish.

I’ve made some version of this dish for years, especially around Thanksgiving, Christmas, and Easter. But honestly? It’s too good to save for holidays. I also make it when we have roast chicken, ham, or even a simple green salad and crusty bread. It feels a little fancy, but it’s still humble. That’s a lovely combination in a recipe, if you ask me.

And while this is definitely a comfort food dish, a few smart choices make it more balanced—using real potatoes, seasoning each layer, and building a sauce that’s creamy without becoming heavy or gluey. That’s the trick. You want rich and creamy potatoes, yes, but you also want clean flavor and a texture that holds together without turning stodgy.

Why you’ll love this recipe

• Creamy, cheesy, and deeply satisfying
• Made with simple grocery-store ingredients
• Perfect for holidays and family dinners
• Easy enough for a weekend meal
• Layers bake up tender, never dry
• The cheese sauce tastes homemade and cozy
• Great make-ahead holiday potato side dish
• Pairs beautifully with ham, roast beef, or chicken
• Reheats surprisingly well the next day
• That golden brown potato gratin top is hard to resist

Ingredients you’ll need

Here’s what you need for this homemade scalloped potatoes au gratin recipe:

• 2 1/2 pounds Yukon Gold potatoes (about 6 to 8 medium potatoes, thinly sliced 1/8 inch thick)

  • Yukon Golds are my favorite because they turn creamy and hold their shape well. Russets work too for a softer, more classic sliced potato casserole feel.

• 3 tablespoons unsalted butter

  • Use real butter for the best flavor. This is the base of the sauce.

• 3 tablespoons all-purpose flour

  • Helps thicken the cream sauce. If needed, you can use a cup-for-cup gluten-free flour blend.

• 2 cups whole milk

  • Whole milk gives the sauce body without making it too heavy.

• 1 cup heavy cream

  • This adds richness and makes the dish feel like true creamy potato gratin.

• 2 cups shredded sharp cheddar cheese, divided

  • Sharp cheddar gives that familiar, cozy flavor. Tillamook and Cabot both melt nicely.

• 1 cup shredded Gruyère cheese, divided

  • Gruyère brings nutty, classic oven baked potato gratin flavor. If it’s pricey in your area, Swiss cheese is a decent substitute.

• 3 garlic cloves, minced

  • Fresh garlic matters here. It gives the sauce depth without overpowering the potatoes.

• 1 1/2 teaspoons kosher salt, divided

  • Seasoning the sauce and layers is important. Potatoes need it.

• 1/2 teaspoon black pepper

• 1/4 teaspoon ground nutmeg

  • Just a little. It won’t taste sweet; it simply rounds out the cream sauce.

• 1 teaspoon fresh thyme leaves (optional)

  • Lovely for a rustic, herby note.

• 1 small onion, very thinly sliced

  • Optional, but I like the gentle sweetness it adds between layers.

• 2 tablespoons grated Parmesan cheese

  • For the top, because that crusty finish is worth it.

• Cooking spray or butter for the baking dish

A quick note on choosing potatoes

For the best baked scalloped potatoes, aim for evenly sized slices so everything cooks at the same rate. A mandoline slicer is handy here—just use the guard, please. I say that like a mother because, well, I am one. Thin, consistent slices make the difference between tender layers and a dish where half the potatoes are soft and half still have bite.

Directions

1. Preheat the oven and prep the dish.
   Heat your oven to 375°F. Grease a 9x13-inch baking dish with butter or cooking spray. Set it aside while you make the sauce and slice the potatoes.

2. Slice the potatoes.
   Peel the potatoes if you like a more classic finish, or leave the skins on for a rustic look. Slice them about 1/8 inch thick. If you’re using onion, slice that very thin too. Keep the potato slices fairly uniform so your layered potato gratin bakes evenly.

3. Start the cheese sauce.
   In a medium saucepan over medium heat, melt the butter. Whisk in the flour and cook for about 1 minute, just until it smells a bit nutty and smooths out. Don’t rush this step; it keeps the sauce from tasting floury.

4. Add the milk and cream.
   Slowly pour in the milk and heavy cream, whisking the whole time. Cook for 3 to 5 minutes until the mixture thickens enough to coat the back of a spoon. Stir in the garlic, 1 teaspoon of salt, black pepper, and nutmeg.

5. Melt in the cheese.
   Lower the heat and add 1 1/2 cups cheddar and 3/4 cup Gruyère. Stir until smooth. The sauce should be creamy and pourable, not stiff. If it seems too thick, add a splash of milk. This is your luscious scalloped potatoes with cheese sauce base.

6. Layer everything up.
   Arrange about one-third of the potatoes in the prepared dish. Top with some onion slices, if using, and spoon over one-third of the cheese sauce. Repeat the layers two more times. Sprinkle a little of the remaining salt lightly between layers so the potatoes are seasoned all the way through.

7. Add the final topping.
   Scatter the remaining cheddar, Gruyère, and Parmesan over the top. If you’re using thyme, add it now. This top layer is what gives you that beautiful golden brown potato gratin finish.

8. Cover and bake.
   Cover the dish with foil and bake for 45 minutes. Then remove the foil and bake another 25 to 35 minutes, until the top is browned and the potatoes are tender when pierced with a knife. You want bubbling edges and a gently bronzed top—those are your cues.

9. Rest before serving.
   Let the gratin rest for 10 to 15 minutes before serving. I know, it smells incredible. But this short rest helps the sauce settle so you can serve neat, creamy portions instead of a runny puddle.

Servings & timing

• Yield: 8 to 10 servings
• Prep Time: 25 minutes
• Bake Time: 70 to 80 minutes
• Rest Time: 10 to 15 minutes
• Total Time: About 1 hour 50 minutes

This makes a generous family dinner potato side and fits nicely into a holiday menu with leftovers to spare.

Variations to keep things interesting

If you like to play around a bit in the kitchen, here are a few easy twists:

• Add cooked ham: Turn it into a hearty main dish with diced ham between the layers.
• Try smoked gouda: Swap part of the cheddar for smoked gouda for a deeper, slightly woodsy flavor.
• Make it extra garlicky: Roast a head of garlic and stir the softened cloves into the sauce.
• Use sweet onions: Vidalia onions add a mellow sweetness that works beautifully here.
• Add greens: Tuck in a layer of baby spinach for a little color and balance.
• Go extra crunchy: Top with buttery breadcrumbs during the last 15 minutes of baking.

Storage & reheating

Leftover cheesy potato casserole stores very well, which is one reason I love it so much.

• Refrigerator: Store covered in the fridge for up to 4 days.
• Freezer: Freeze tightly wrapped portions for up to 2 months. The texture may soften a bit after thawing, but it will still taste lovely.
• Reheating: Warm individual portions in the microwave in 60-second bursts, or reheat the full dish covered in a 350°F oven until hot, about 20 to 25 minutes.
• Make-ahead tip: Assemble the dish up to 24 hours in advance, cover, and refrigerate. Add about 10 extra minutes to the baking time if it’s going into the oven cold.

Notes from my kitchen

A few things I learned while testing this easy scalloped potatoes recipe over the years:

First, don’t use pre-shredded cheese if you can help it. It’s convenient, yes, and I’m not above convenient. But bagged cheese often has anti-caking agents that keep the sauce from turning silky. Freshly shredded cheese melts better. It just does.

Second, slice the potatoes thinly and evenly. That one detail solves a lot of problems before they start. If your slices are too thick, the sauce can split while the potatoes are still trying to soften. Nobody wants that.

Third, let the dish rest. I know I mentioned it already, but it matters. A gratin fresh from the oven is bubbling and loose; after 10 or 15 minutes, it becomes creamy, sliceable, and much more elegant on the plate.

And one more thing—salt the layers lightly. Potatoes are mild, which is part of their charm, but they need seasoning to shine. A well-seasoned potatoes in cream sauce dish tastes rich and balanced, not flat.

FAQs

Can I make scalloped potatoes au gratin ahead of time?

Yes. You can assemble the dish a day ahead, cover it, and refrigerate it until you’re ready to bake.

What’s the difference between scalloped potatoes and au gratin potatoes?

Traditionally, scalloped potatoes are baked in a cream-based sauce, while au gratin includes cheese. In home kitchens, the names are often used together, especially for a cheesy version like this.

Do I have to peel the potatoes?

No, not at all. Peeled potatoes give a smoother, classic look, but unpeeled Yukon Golds make a lovely rustic potato gratin.

Why are my potatoes still hard after baking?

They were likely sliced too thick, or the dish needed more covered baking time. Check with a knife in the center, not just around the edges.

Can I use only one kind of cheese?

Absolutely. Sharp cheddar alone works well, though adding Gruyère gives the dish a more traditional classic potato au gratin flavor.

How do I keep the sauce from curdling?

Use moderate heat, don’t boil the sauce hard, and stick with full-fat dairy for the smoothest result.

Can I freeze leftovers?

Yes, though cream sauces can change texture slightly after thawing. Reheat gently and stir if needed.

What should I serve with this dish?

It’s wonderful with baked ham, roast turkey, pork tenderloin, meatloaf, or even a crisp salad if you want the meal to feel a little lighter.

A cozy side dish worth making again and again

This Scalloped Potatoes Au Gratin Recipe is creamy, cheesy, comforting, and dependable—the kind of recipe that earns a permanent spot in your dinner rotation. Whether you’re planning a holiday feast or simply want a warm, satisfying side for Sunday supper, this dish brings all that rich, homemade goodness to the table.

If you make it, I’d love to hear how it turned out for you. Leave a comment, share your favorite variation, and if you’re in the mood for more comfort food, take a peek at other classic side dishes and cozy family dinner recipes too.