Potatoes Au Gratin

Potatoes au gratin makes the perfect potato side dish for Sunday supper or as a make-ahead holiday side dish! Layers of potatoes and onions are baked in a rich, cheesy sauce until bubbly and golden brown.

This Potatoes au Gratin recipe makes easy cheesy potatoes, similar to scalloped potatoes but loaded with rich cheesy flavor. They are the perfect holiday dish next to a baked ham or even Roast Beef Tenderloin or pork tenderloin!

• Flavor: Creamy, cheesy, and comforting with a golden, slightly crispy top that makes every bite irresistible.
• Recommended Tools: To save time on prep and make even and thin potato and onion slices, use a mandoline or the side of a box grater.
• Budget Tip: You can swap Gruyère for provolone or Swiss and still get that melty, flavorful goodness.
• Time-Saving Tip: If you’re short on time, check the recipe notes below to reduce cooking time.

So what is the difference between scalloped potatoes and au gratin potatoes? They’re both very similar, containing potatoes (and often onions) baked in a creamy sauce. Au Gratin is defined as covered with breadcrumbs or cheese, scalloped refers to “bake with milk or a sauce”.

In the case of this recipe, the difference is the cheese. That being said, the term scalloped potatoes is still often still used if there is cheese within the dish!

The Best Kind of Potato to Use for Potatoes au Gratin

Just like when making scalloped potatoes, the best potatoes for gratin are red-skinned or Yukon gold potatoes. These two waxy potatoes can hold their shape well and because they’re thin-skinned, they do not require peeling (extra bonus!).

While russet potatoes or baking potatoes taste good, they’re more starchy. They do not hold their shape as well and the dish can become mushy, they’re more suited to mashed potatoes.

Cheese for Potatoes au Gratin

What is the best cheese for potatoes au gratin?  When making Gratin potatoes, choose cheeses that have lots of bold flavors.  Our top choices are varieties with a sharper flavor including sharp cheddar and Gruyere.

Gruyere cheese adds a rich flavor to au gratin potatoes that truly cannot be matched; if you can get it, I highly recommend that you do! If Gruyere isn’t available use provolone or swiss for a similar flavor!

How to Make Potatoes Au Gratin

Potatoes Au Gratin has tender potatoes in a creamy, cheesy sauce for a dish that everyone loves.

1. Prep: Thinly slice the potatoes and onions.
2. Assemble: Stack the potato slices and onions in little piles and then stand them on their sides in the casserole dish.
3. Sauce: Cook the cheese sauce in a saucepan over medium heat until smooth and creamy (full recipe below), then pour it over the potato and onion slices.
4. Bake: Bake until the potatoes are tender and the sauce is bubbly.

• Pre-shredded cheese will work in this recipe; however, the sauce will be smoother if you shred cheese from a block.
• If swapping the cheese, make sure you use varieties that have bold flavors.
• For a quicker version, layer potatoes and onions, cover, and microwave 10 minutes. Add cheese sauce and bake 45–55 minutes as directed. Just as delicious, but a little quicker!
• Make up to 24 hours ahead. Keep potatoes covered in sauce, cover tightly, and refrigerate. Bring to room temperature before baking, and add 10–20 minutes to the bake time.
• While we often eat these as a side, I sometimes include leftover ham before baking and serve it as a main.

Second Day Servings

• Leftover potatoes au gratin will keep in the refrigerator for up to 4 days. Let it cool completely, then cover tightly with plastic wrap, or transfer to an airtight container before refrigerating.
• To freeze, allow it to cool completely and wrap the dish well with both plastic wrap and aluminum foil, or portion it into freezer-safe containers. It will keep for up to 2 months in the freezer.
• For best results, thaw overnight in the refrigerator before reheating. Reheat covered in the oven at 350°F until hot throughout (about 20 to 30 minutes), removing the cover near the end to crisp up the top again.
• Avoid microwaving frozen potatoes, as it can make the sauce grainy and the potatoes watery.

More Holiday Side Dishes

Did you make this Potatoes au Gratin recipe? Leave us a rating and a comment below.

Prep Time 20 minutes minutes

Cook Time 1 hour hour 30 minutes minutes

Cool Time 15 minutes minutes

Total Time 2 hours hours 5 minutes minutes

• Preheat oven to 400°F.

• Wash potatoes and slice into ⅛” thin slices. Slice onion as thinly as possible.

• Season the potatoes and onions with ½ teaspoon of salt and ¼ teaspoon of pepper. Toss well to evenly coat. Layer potatoes and onions into little stacks. Place stacks on their side in a greased 2.5QT to 3QT casserole dish.

• In a saucepan, melt butter and flour and cook for 2 to 3 minutes. Add mustard powder, ¼ teaspoon salt, ¼ teaspoon pepper, and milk. Whisk over medium heat until thick and bubbly. Remove from heat and stir in cheeses until melted.

• Pour the cheese sauce over the potatoes, gently separating the stacks to allow the sauce to seep between the layers. Cover with foil (sprayed with cooking spray) and bake for 60 minutes.

• Remove foil and bake an additional 20 to 30 minutes or until lightly browned and potatoes are cooked. Cool 15 minutes before serving.

• Slice potatoes as thinly as possible.
• Shred your own cheese from a block for the best results. Fresh herbs (such as thyme or rosemary) and garlic can be added to the sauce if desired.
• To reduce baking time, wrap a microwave-safe casserole dish in plastic wrap before adding the cheese sauce and microwave on full power for about 10 minutes (be careful, it will be hot when removing the plastic wrap). Add the cheese sauce and bake as directed for about 45-55 minutes.
• Additional cheese (cheddar or parmesan) can be sprinkled on top once the foil is removed if desired.
• Store leftovers in an airtight container for up to 4 days. Reheat in the oven or the microwave.

Calories: 271 | Carbohydrates: 30g | Protein: 11g | Fat: 13g | Saturated Fat: 7g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 3g | Trans Fat: 0.2g | Cholesterol: 37mg | Sodium: 452mg | Potassium: 784mg | Fiber: 3g | Sugar: 5g | Vitamin A: 478IU | Vitamin C: 13mg | Calcium: 278mg | Iron: 1mg

Nutrition information provided is an estimate and will vary based on cooking methods and brands of ingredients used.

Course Side Dish
Cuisine American, French

© SpendWithPennies.com. Content and photographs are copyright protected. Sharing of this recipe is both encouraged and appreciated. Copying and/or pasting full recipes to any social media is strictly prohibited. Please view my photo use policy here.