Scalloped Potatoes Au Gratin Recipe

There’s something downright comforting about a bubbling dish of Scalloped Potatoes Au Gratin Recipe fresh from the oven—creamy layers of tender potatoes, plenty of cheese, and that golden, toasty top that makes everyone hover near the kitchen.

A Cozy Classic That Never Goes Out of Style

If you’ve ever wondered what makes a great Scalloped Potatoes Au Gratin Recipe so memorable, it’s that balance of simple pantry ingredients and full, rich flavor. This is one of those classic American comfort food recipes that shows up at Easter, Thanksgiving, Christmas dinner, Sunday supper, and honestly, any chilly weeknight when you want a side dish that feels a little extra special.

Now, technically, some folks separate scalloped potatoes from potatoes au gratin. Traditional scalloped potatoes are often made with a cream-based sauce, while Potatoes Au Gratin usually include cheese. But in many home kitchens—mine included—we tend to blend the two ideas into one glorious cheese potato bake. And I’m not mad about it one bit.

What makes this baked potato dish stand out is the texture. The potatoes turn soft and silky without falling apart, and the sauce becomes velvety, not gluey. The top gets browned and bubbly, and those crispy bits around the edges? Well, if you know, you know. That’s the cook’s reward.

I like serving this potato casserole with baked ham, roast chicken, pork tenderloin, or even a simple green salad when I want dinner to feel complete without a lot of extra fuss. It’s not exactly “light,” but it is deeply satisfying, and there’s room in life for that. Especially when the weather cools off or the holiday table needs a dependable, crowd-pleasing side dish recipe.

Why You’ll Love This Recipe

Rich, creamy, and wonderfully cheesy
Uses everyday grocery store ingredients
Perfect for holidays, potlucks, or Sunday dinner
Make-ahead friendly for less stress
Feeds a crowd without feeling fussy
Bakes up golden and beautiful every time
Pairs well with ham, turkey, beef, or chicken
Easy to customize with herbs, onions, or extra cheese

Comfort food at its finest
Leftovers reheat surprisingly well

Ingredients You’ll Need

Here’s everything you need for this homemade Au Gratin Recipe, along with a few little tips I’ve learned after making this more times than I can count.

2 1/2 pounds Yukon Gold potatoes (about 6 medium potatoes, thinly sliced 1/8 inch thick)
Yukon Golds are my favorite for creamy potatoes because they hold their shape and have a buttery flavor. Russets work too and give a softer, starchier result.

2 tablespoons unsalted butter
Use this for greasing the dish and starting the sauce. If using salted butter, reduce the added salt slightly.
1 small yellow onion, very finely diced
This adds sweetness and depth without overpowering the potatoes. A shallot works nicely too if you want a gentler onion flavor.
2 cloves garlic, minced
Fresh garlic gives the best flavor. Garlic powder can work in a pinch—use 1/2 teaspoon.
3 tablespoons all-purpose flour
This thickens the sauce so it coats the potato layers well. For gluten-free needs, use a 1:1 gluten-free flour blend.
2 cups whole milk
Whole milk gives body without making the sauce too heavy. I’ve tested 2% milk, and it works, though the sauce is a bit less lush.
1 cup heavy cream
This is what gives the dish that classic Potatoes Au Gratin richness. You can swap with half-and-half for a slightly lighter version.

1 teaspoon kosher salt
Potatoes need seasoning. Don’t skip this or the dish can taste flat.
1/2 teaspoon black pepper
Freshly cracked pepper adds a warmer, more rounded flavor.
1/2 teaspoon paprika
This adds subtle color and just a hint of warmth.

1 teaspoon fresh thyme leaves (or 1/2 teaspoon dried thyme)
Optional, but lovely. It gives the casserole a little savory backbone.
2 cups shredded sharp cheddar cheese
Sharp cheddar brings strong flavor and good melt. Tillamook and Cabot are both dependable here.
1 cup shredded Gruyère cheese
Gruyère melts beautifully and gives that classic gratin potatoes flavor. If it’s pricey where you live, Swiss cheese is a fair substitute.

2 tablespoons grated Parmesan cheese
Sprinkle this on top for extra browned, savory goodness.
Cooking spray or a little extra butter for the baking dish

How to Make Scalloped Potatoes Au Gratin

Preheat the oven and prep the dish.
Set your oven to 375°F. Grease a 9×13-inch baking dish with butter or cooking spray. This helps prevent sticking and gives those edges a nice golden finish.

Slice the potatoes evenly.
Thinly slice the potatoes to about 1/8 inch. A mandoline makes this fast and consistent, but a sharp knife works too—just keep the slices as even as you can so they bake at the same rate.
Start the sauce with onion and garlic.
In a medium saucepan, melt the butter over medium heat. Add the onion and cook for 3 to 4 minutes, until softened. Stir in the garlic and cook for 30 seconds. Don’t let it brown; burnt garlic can turn bitter in a hurry.
Build the creamy base.
Sprinkle in the flour and whisk for about 1 minute. Slowly pour in the milk and cream, whisking the whole time so the sauce stays smooth. Add salt, pepper, paprika, and thyme. Cook for 4 to 5 minutes, stirring often, until the sauce thickens slightly. It should coat the back of a spoon, not sit there like paste.

Melt in the cheese.
Remove the pan from the heat and stir in 1 1/2 cups cheddar and 3/4 cup Gruyère until melted. The sauce will be silky and smell like something everybody wants a spoonful of immediately.
Layer the potatoes and sauce.
Arrange half the sliced potatoes in the prepared baking dish. Pour over half the cheese sauce. Repeat with the remaining potatoes and sauce. Gently press down with a spatula so the sauce seeps between the layers.
Add the topping.
Sprinkle the remaining cheddar, remaining Gruyère, and Parmesan evenly over the top. This is where the magic happens—that golden crust, that bubbling cheese, the whole cozy situation.

Bake covered first.
Cover the dish loosely with foil and bake for 45 minutes. Covering it early traps steam and helps the potatoes soften before the top gets too dark.
Finish uncovered.
Remove the foil and bake another 25 to 30 minutes, until the top is deeply golden and the potatoes are fork-tender. If you want extra browning, broil for 1 to 2 minutes at the very end, but watch it like a hawk.
Let it rest before serving.
Rest the casserole for 10 to 15 minutes before spooning it out. I know, it’s hard to wait. But that little pause helps the sauce settle so you get neat, creamy servings instead of a runny puddle.

Servings & Timing

Yield: 8 to 10 servings
Prep Time: 25 minutes
Bake Time: 70 to 75 minutes
Rest Time: 10 to 15 minutes
Total Time: About 1 hour 50 minutes

For holidays, I usually count on 8 generous servings. If you’re serving it among several sides, you can comfortably stretch it to 10.

Variations to Try

If you like to tinker a little in the kitchen—and I always do—here are a few easy ways to change up this Scalloped Potato Recipe.

Add bacon: Sprinkle cooked chopped bacon between the layers for a smoky, savory spin.

Try smoked cheese: Swap part of the cheddar with smoked gouda for a deeper, richer flavor.
Make it onion-forward: Add thinly sliced caramelized onions for sweetness and extra depth.
Go herby: Mix in rosemary or chives for a fresher, more garden-style finish.

Lighten it a touch: Use half-and-half instead of heavy cream for a slightly less rich casserole.
Add ham: Fold in diced cooked ham to turn this oven baked potatoes dish into a full meal.

Storage & Reheating

This comfort food recipe stores beautifully, which is one reason I love it so much.

Refrigerator: Store leftovers in an airtight container or tightly covered baking dish for up to 4 days.
Freezer: Freeze in portions or as a whole baked casserole for up to 2 months. Wrap well to prevent freezer burn.
Reheating: Warm individual portions in the microwave for 1 to 2 minutes, or reheat the full dish in a 350°F oven covered with foil for about 20 to 25 minutes.

Thawing: If frozen, thaw overnight in the refrigerator before reheating for best texture.
Make-ahead tip: Assemble the casserole up to 24 hours ahead, cover tightly, and refrigerate. Let it sit at room temperature for about 30 minutes before baking.

One little note: the sauce thickens more after chilling, which is normal. A splash of milk before reheating can help restore creaminess.

Notes From My Kitchen

I’ve tested this Homemade Au Gratin a few different ways, and a few details really matter.

First, slice the potatoes evenly. It sounds obvious, I know, but uneven slices are usually the reason one part turns mushy while another stays too firm. A mandoline slicer, even an inexpensive OXO one, can make a big difference.

Second, don’t use pre-shredded cheese if you can help it. Those bagged cheeses contain anti-caking agents, and they don’t melt quite as smoothly. Freshly shredded cheese gives you the best creamy texture and that lovely stretch when you serve it.

Third, season the sauce well before layering. Potatoes soak up flavor like a sponge. If the sauce tastes slightly more seasoned than you’d normally expect, that’s usually just right once everything bakes together.

And finally, let it rest. I’m repeating myself, yes, but for good reason. Resting is the difference between a loose cheesy potatoes casserole and one that slices and serves beautifully.

FAQs

Can I make scalloped potatoes au gratin ahead of time?

Yes, absolutely. You can assemble the whole dish a day ahead, refrigerate it, and bake it the next day. It’s a great holiday trick when oven space and time get tight.

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

Traditionally, scalloped potatoes use a cream sauce, while potatoes au gratin include cheese. This recipe blends both styles, which is why it’s especially rich and flavorful.

Why are my potatoes still hard after baking?

The slices may have been too thick, or the dish may have needed more covered baking time. Make sure your potatoes are sliced thinly and bake covered long enough for steam to soften them.

Can I use russet potatoes instead of Yukon Gold?

Yes, you can. Russets create a softer, more classic casserole texture, while Yukon Golds hold their shape a bit better and taste more buttery.

Why did my sauce turn grainy?

Graininess usually comes from overheating the cheese sauce or using pre-shredded cheese. Remove the sauce from the heat before stirring in the cheese, and shred your own for the smoothest result.

Can I freeze this potato casserole?

Yes. Bake it first, cool it fully, then wrap and freeze. The texture may soften a little after thawing, but it still tastes delicious.

What cheese works best for au gratin potatoes?

A mix of sharp cheddar and Gruyère is excellent because it gives both flavor and melt. Swiss, fontina, or Monterey Jack can also work well.

How do I keep the top from browning too quickly?

Bake the dish covered for the first part of cooking, then uncover it later. If the top still browns too fast, lay foil loosely over it for the remainder of baking.

A Few Extra Serving Ideas

This side dish recipe pairs especially well with:

glazed ham
roast turkey
grilled steak
pork chops
roasted green beans
a crisp salad with vinaigrette

If you’re building out a holiday menu, you might also want to add homemade dinner rolls, a tart cranberry dish, or roasted Brussels sprouts for contrast. Rich creamy potatoes always appreciate something fresh and bright on the plate.

Conclusion

This Scalloped Potatoes Au Gratin Recipe is everything a classic baked potato dish should be—creamy, cheesy, golden, and deeply comforting. It’s reliable enough for holidays, easy enough for family dinners, and delicious enough that folks will ask for it again and again.

If you try it, I’d love for you to leave a comment and share how it turned out. And if you’re planning a full comfort-food meal, take a peek at my other cozy side dish recipes and old-fashioned casseroles too.