Au Gratin Potatoes Recipe

This au gratin potatoes recipe layers 2 pounds of paper-thin Yukon Gold slices with a Gruyère and cheddar sauce, then finishes under a panko and Parmesan crust.

A butter and flour roux keeps the milk and cream from splitting in the oven. The top finishes with extra Gruyère for a crisp, golden crust over a creamy center.

Many versions turn out watery or leave firm potatoes in the middle. Slicing at 1/8 inch and covering the dish for the first 45 minutes prevents both.

This one serves 8 and needs about 1 hour 45 minutes from the first slice to the end of the bake, plus a 15-minute rest.

Quick Recipe Summary
Prep Time	30 minutes
Cook Time	1 hour 15 minutes
Total Time	1 hour 45 minutes
Servings	8 servings
Difficulty Level	Easy

Read Also: Scalloped Potatoes Recipe

Jump to Recipe

Why You’ll Love This Au Gratin Potatoes Recipe

This version follows the classic method, with a stovetop cheese sauce poured over raw sliced potatoes. Everything bakes in one dish and serves 8.

• Reliable texture: The roux-thickened sauce clings to every slice instead of pooling at the bottom of the dish.
• Two cheeses: Gruyère brings a nutty, smooth melt, and sharp cheddar adds tang.
• Crisp top: Panko, Parmesan, and extra cheese brown into a crunchy layer that contrasts with the soft potatoes underneath.
• One baking dish: The sauce is made in a single saucepan, so cleanup stays minimal.
• Make-ahead friendly: You can assemble the gratin a day early and bake it when the oven frees up.
• Pairs with big mains: It sits comfortably next to ham, prime rib, turkey, and roast chicken.

A simpler cheese and potato casserole is Cheesy Potatoes Recipe.

Ingredients

Every ingredient below is used in the instructions, and the butter and cheeses are divided between the sauce and the topping. Read the notes in parentheses before you start.

For the potatoes and sauce:

• 2 pounds (900 g) Yukon Gold potatoes (about 6 medium), peeled and sliced 1/8 inch (3 mm) thick
• 5 tablespoons (70 g) unsalted butter, divided (3 tablespoons for the sauce, 1 tablespoon for greasing the dish, 1 tablespoon melted for the topping)
• 1 small yellow onion (about 1/2 cup or 75 g), finely diced
• 2 cloves garlic, minced
• 3 tablespoons (24 g) all-purpose flour
• 1 1/2 cups (360 ml) whole milk
• 1 cup (240 ml) heavy cream
• 1 teaspoon kosher salt
• 1/2 teaspoon freshly ground black pepper
• 1/4 teaspoon freshly grated whole nutmeg
• 1 teaspoon fresh thyme leaves
• 1 1/2 cups (6 oz or 170 g) shredded Gruyère cheese, divided (1 cup for the sauce, 1/2 cup for the topping)
• 1 cup (4 oz or 113 g) shredded sharp cheddar cheese, divided (3/4 cup for the sauce, 1/4 cup for the topping)

For the topping:

• 1/2 cup (30 g) panko breadcrumbs
• 1/4 cup (25 g) finely grated Parmigiano-Reggiano
• 1 tablespoon chopped fresh parsley, for garnish

You might also enjoy: Funeral Potatoes Recipe

Kitchen Equipment Needed

You do not need specialty gear, but even slices make the biggest difference, so a good slicer is worth having. Everything else is likely already in your kitchen.

• Mandoline slicer for uniform 1/8-inch potato slices
• Chef’s knife for dicing the onion and mincing the garlic
• 2-quart baking dish, an 8×8-inch (20 cm) or 9×9-inch (23 cm) dish
• Heavy-bottomed saucepan (3 quarts works well) for the roux and sauce
• Whisk for a lump-free sauce
• Box grater for shredding the Gruyère and cheddar
• Rimmed baking sheet to catch any bubbling sauce
• Aluminum foil for covering the dish during the first bake
• Cutting board, measuring cups and spoons, a small bowl for the topping, and a wooden spoon

For another potato dish that rewards a little patience, see Twice Baked Potatoes Recipe.

Recommended Products for This Recipe

These are the tools and ingredients I recommend because each one solves a specific problem that comes up with this dish. None of them are required, but they make the result more consistent.

1. OXO Good Grips Chef’s Mandoline Slicer

Hand-cut slices vary in thickness, which leaves some potatoes mushy and others firm in the same dish. A mandoline with a thickness dial lets you lock in 1/8 inch and cut 2 pounds of potatoes in a few minutes.

Get it on Amazon

2. Emile Henry Gratin Dish

Thin metal pans can scorch the bottom layer before the center cooks through. A thick ceramic dish heats gently and evenly, and it goes straight from the oven to the table.

Get it on Amazon

3. Le Gruyère AOP Cheese

Mild, generic “Swiss-style” cheese gives the sauce very little character. Authentic Gruyère AOP melts smoothly and adds the nutty, slightly sweet flavor that defines a classic gratin.

Get it on Amazon

4. Cut-Resistant Gloves

Mandoline blades are sharp, and the last few inches of a potato are the easiest place to slip. A cut-resistant glove protects your fingertips and lets you keep slicing past the point where most people stop.

Get it on Amazon

For more potato ideas, try: Potato Side Dish Recipes

Step-by-Step Instructions: How to Make Au Gratin Potatoes

Follow these steps in order and the potatoes will bake up tender, creamy, and golden on top.

1. Prep the Oven and Baking Dish

• Move an oven rack to the middle position and preheat the oven to 375°F (190°C).
• Use 1 tablespoon of the butter to grease the bottom and sides of an 8×8-inch or 9×9-inch baking dish, covering every corner so the sauce does not stick.
• Set the dish on a rimmed baking sheet. This catches any sauce that bubbles over and makes the dish easier to move in and out of the oven.

2. Slice the Potatoes

• Peel the potatoes with a vegetable peeler and trim off any dark spots.
• Set a mandoline to 1/8 inch (3 mm). Use the hand guard or a cut-resistant glove and slice the potatoes into even rounds.
• Place the slices in a large bowl and keep them together. Do not rinse them, because the surface starch helps thicken the sauce as it bakes.
• Slice the potatoes just before assembling. If you must slice ahead, hold them in cold water and pat them completely dry before layering.

3. Shred and Divide the Cheeses

• Shred 1 1/2 cups of Gruyère and 1 cup of sharp cheddar on the large holes of a box grater.
• In one bowl, combine 1 cup of the Gruyère and 3/4 cup of the cheddar. This is the sauce cheese.
• In a second bowl, combine the remaining 1/2 cup of Gruyère and 1/4 cup of cheddar. This is for the topping.
• Add the Parmigiano-Reggiano and panko to the second bowl, but do not add the melted butter yet.

4. Cook the Onion and Garlic

• Melt 3 tablespoons of butter in a heavy 3-quart saucepan over medium heat.
• Add the diced onion and cook for 4 to 5 minutes, stirring often, until soft and translucent but not browned.
• Stir in the garlic and cook for 30 seconds, just until fragrant. Garlic burns quickly, so move to the next step right away.

5. Make the Roux and Cheese Sauce

• Sprinkle the 3 tablespoons of flour over the onion and butter. Whisk constantly for 1 to 2 minutes so the raw flour taste cooks out and the mixture looks like a thick paste.
• Pour in the milk very slowly while whisking, about 1/4 cup at a time at first. Adding it gradually prevents lumps.
• Whisk in the heavy cream. Raise the heat to medium-high and bring the sauce to a gentle bubble, whisking often.
• Reduce the heat to medium and simmer for 3 to 4 minutes, until the sauce is thick enough to coat the back of a spoon.
• Remove the saucepan from the heat. Stir in the salt, pepper, nutmeg, and thyme.
• Add the sauce cheese (1 cup Gruyère and 3/4 cup cheddar) a handful at a time, stirring after each addition until fully melted and smooth.

6. Layer the Gratin

• Spread one-third of the potato slices across the bottom of the greased dish, overlapping them slightly so there are no gaps.
• Spoon one-third of the cheese sauce over the potatoes and spread it to the edges.
• Repeat with another third of the potatoes and another third of the sauce.
• Finish with the last of the potatoes and the remaining sauce, pushing the sauce into any dry spots so every slice is coated.
• Press down gently with the back of a spatula so the layers sit flat and the sauce rises between the slices.

7. Bake Covered

• Cover the dish tightly with foil, crimping the edges. This traps steam so the potatoes cook through without drying out.
• Slide the baking sheet with the dish into the oven and bake for 45 minutes.
• Carefully lift one corner of the foil away from you to release the steam and check that the sauce is bubbling around the edges.

8. Add the Topping and Bake Uncovered

• Melt the last tablespoon of butter and toss it with the panko, Parmigiano-Reggiano, remaining 1/2 cup of Gruyère, and remaining 1/4 cup of cheddar until the crumbs look evenly moistened.
• Remove the foil and scatter the topping evenly over the surface.
• Return the dish to the oven and bake, uncovered, for 25 to 30 minutes, until the top is deeply golden and the sauce is bubbling at the edges.
• Test the center with a paring knife. It should slide through the potatoes with almost no resistance.
• If the top browns before the potatoes are tender, tent the dish loosely with foil and bake another 5 to 10 minutes.

9. Rest and Serve

• Remove the dish from the oven and let it rest for 15 minutes. The sauce thickens as it cools slightly, which lets you cut clean squares.
• Sprinkle the chopped parsley over the top.
• Cut into 8 portions and lift each one with a wide spatula so the layers stay intact.

Read Also: Mashed Potatoes Recipe

Tips for The Best Au Gratin Potatoes

A few small details separate a creamy, sliceable gratin from a runny or undercooked one. These are the ones that matter most.

• Slice evenly at 1/8 inch. I ruined my first batch by cutting the potatoes by hand with a knife, which left raw slices sitting next to mushy ones. Switching to a mandoline set at 1/8 inch fixed it immediately.
• Choose Yukon Golds. They hold their shape better than russets in this dish because they are less starchy, so the layers stay distinct while the slices still turn creamy.
• Do not rinse the slices. The surface starch thickens the sauce, and washing it off can leave the gratin thinner.
• Shred the cheese yourself. Pre-shredded cheese is coated to prevent clumping, and that coating can make the sauce slightly grainy. I keep a block of Gruyère in the freezer for 15 minutes before grating because the firmer cheese shreds cleanly instead of smearing on the grater.
• Add the cheese off the heat. I’ve found that stirring in cheese after removing the pan from the burner produces a smoother sauce than adding it over direct heat, which can make it grainy or greasy.
• Whisk in the milk slowly. Pouring the liquid into the roux a little at a time prevents lumps and gives a glossy sauce.
• Season the sauce well. The potatoes absorb a lot of salt, so a sauce that tastes slightly seasoned on its own will taste balanced once baked.
• Keep the foil tight. Steam does most of the work in the first 45 minutes, so crimp the edges all the way around.
• Use a baking sheet. Sauce can bubble over the edge of a full dish, and the sheet saves your oven floor.
• Check with a knife, not the clock. Ovens vary, so if the potatoes still resist after the uncovered bake, cover the dish again and bake 10 more minutes.
• Never skip the rest. A 15-minute rest lets the sauce set so the portions hold together on the plate.

A similar stovetop sauce made on its own is covered in Cheese Sauce Recipe.

What to Serve with Au Gratin Potatoes

Au gratin potatoes are rich, so they pair best with simple proteins and bright or crisp vegetables that balance the cream and cheese. These pairings cover everything from weeknight dinners to holiday tables.

• Honey Glazed Ham: The sweet, salty glaze plays well against the nutty cheese sauce.
• Prime Rib: A classic holiday pairing, where the potatoes soak up the beef juices on the plate.
• Roast Chicken: Crisp skin and savory pan juices suit the creamy layers.
• Thanksgiving Turkey: The gratin is a sturdy side that holds heat well on a crowded table.
• Filet Mignon: A tender steak and a rich potato side make a restaurant-style dinner.
• Rack of Lamb: The herbal notes in lamb echo the thyme in the sauce.
• Apple Cider Glazed Pork Chops: The tangy glaze cuts through the cream.
• Green Bean Casserole: A familiar holiday vegetable side with a crunchy topping.
• Roasted Brussels Sprouts with Bacon: Caramelized edges and smoky bacon add contrast.
• Maple Glazed Carrots: Sweet, tender carrots add color to the plate.
• A crisp green salad with lemon vinaigrette: The acidity refreshes the palate between rich bites.
• Steamed asparagus with a squeeze of lemon: A light vegetable that keeps the meal from feeling heavy.
• A glass of Chardonnay or Pinot Noir: Both have enough acidity to balance the cheese and cream.

Another ham and potato pairing: Scalloped Potatoes and Ham Recipe

Variations of Au Gratin Potatoes

The classic version is hard to beat, but the basic method adapts easily. Keep the potato quantity and sauce ratio the same, and change one element at a time.

• All Gruyère: Replace the cheddar with an equal amount of Gruyère for a milder, nuttier sauce that tastes closer to a French gratin.
• Sharp cheddar only: Use 2 1/2 cups of sharp cheddar in total for a tangier, more American-style gratin.
• Smoked Gouda: Swap the cheddar for smoked Gouda to add a gentle smokiness that works well with ham or pork.
• Ham and potato: Layer 1 1/2 cups of diced cooked ham between the potato layers for a one-dish main course.
• Bacon topping: Stir 4 slices of cooked, crumbled bacon into the panko topping before the uncovered bake.
• Leeks instead of onion: Use 1 cup of thinly sliced, well-rinsed leeks in place of the diced onion and cook them until soft.
• Extra garlic and herbs: Add a third clove of garlic and swap in fresh rosemary for the thyme, using about 1/2 teaspoon, chopped fine.
• Sweet potato blend: Replace half of the Yukon Golds with sweet potatoes sliced to the same thickness for a slightly sweeter dish.
• Gluten-free: Use a 1-to-1 gluten-free flour blend for the roux and gluten-free panko for the topping.
• No breadcrumb crust: Skip the panko and Parmigiano-Reggiano mixture and top with only the remaining Gruyère and cheddar for a softer, cheesy top.

Read Also: Hashbrown Casserole Recipe

Storage and Reheating

This gratin keeps well and often tastes even better the next day, once the sauce has set and the flavors have blended. Store it properly and reheat it gently to protect the texture.

• Refrigerator: Cool the gratin to room temperature, then cover tightly or transfer portions to airtight containers. It keeps for up to 4 days.
• Oven reheating: Place portions in a baking dish, cover with foil, and reheat at 350°F (175°C) for 20 to 25 minutes. Remove the foil for the last 5 to 10 minutes so the top crisps again.
• Microwave reheating: Heat a single portion on medium power for 1 to 2 minutes, rest it for 30 seconds, then heat in 30-second bursts until hot in the center. The topping will be softer this way.
• Freezing: Freeze baked, cooled portions in airtight containers for up to 2 months. Dairy sauces can turn slightly grainy after freezing, so expect a small change in texture.
• Thawing: Thaw frozen portions overnight in the refrigerator before reheating in the oven.
• Make-ahead assembly: Prepare the gratin through step 6, cover tightly, and refrigerate for up to 24 hours. Keep the topping in a separate container.
• Baking from cold: Bake the chilled gratin covered for 55 to 60 minutes instead of 45, then add the topping and finish uncovered as written.

Another make-ahead cheesy bake worth a look is Baked Mac and Cheese Recipe.

Nutritional Facts

The values below are estimates for one of 8 servings. Actual numbers vary with the brands of cheese and cream you use.

Nutrition per Serving (1 of 8)
Calories	460 kcal
Total Fat	32 g
Saturated Fat	19 g
Carbohydrates	27 g
Fiber	2 g
Sugar	4 g
Protein	16 g
Sodium	570 mg

For a lighter option, try: Healthy Mashed Potatoes Recipe

Health Benefits of Key Ingredients

Au gratin potatoes are an indulgent side dish, but the main ingredients do contribute real nutrients. Enjoying a moderate portion alongside vegetables and lean protein keeps the meal balanced.

• Yukon Gold potatoes: Potatoes are a good source of potassium, vitamin C, and vitamin B6, and they supply energy-giving carbohydrates.
• Gruyère cheese: This firm cheese is a concentrated source of calcium and protein, both important for bones and muscle.
• Sharp cheddar: Cheddar adds more calcium and protein, along with vitamin B12.
• Whole milk: Milk provides calcium and protein, and many brands are fortified with vitamin D.
• Heavy cream: Cream contributes vitamin A, but it is also high in saturated fat, which is why portion size matters in this dish.
• Onion and garlic: Both contain sulfur compounds, and onions also provide flavonoids such as quercetin.
• Parmigiano-Reggiano: A small amount adds protein and calcium and a savory depth that lets you use less salt elsewhere.
• Fresh thyme and parsley: The herbs add flavor and aroma without adding sodium or calories.

Read Also: Best Potato Recipes

FAQs About Au Gratin Potatoes

1. What is the difference between au gratin potatoes and scalloped potatoes?

Au gratin potatoes include cheese in the sauce and often carry a cheese or breadcrumb topping. Scalloped potatoes are traditionally baked in cream or milk without cheese.

Many home cooks use the terms interchangeably, so you will see cheesy recipes labeled both ways. This recipe is au gratin because of the Gruyère, cheddar, and panko crust.

2. Why are my au gratin potatoes still hard?

Slices that are too thick or a dish that was not covered tightly are the usual causes. Aim for 1/8-inch slices and keep the foil sealed for the full 45 minutes.

If a knife still meets resistance after the uncovered bake, cover the dish again and bake 10 more minutes.

3. Can I make au gratin potatoes ahead of time?

Yes. Assemble the gratin without the topping, cover it tightly, and refrigerate for up to 24 hours.

Bake it covered for 55 to 60 minutes instead of 45, then add the topping and finish uncovered.

4. What are the best potatoes for au gratin?

Yukon Golds are the best choice because they stay creamy and keep distinct layers. Russets work too, though their slices break down more and the layers look less defined.

5. Do I need to peel the potatoes?

Peeling is optional. Leaving the skins on saves time and adds a slightly earthier flavor.

This recipe peels the potatoes for the smoothest texture and the cleanest look against the white sauce.

6. Why is my sauce watery or greasy?

A thin sauce usually means the roux was undercooked or the sauce was not simmered long enough. Greasy sauce usually means the cheese went in over high heat.

Cook the roux for a full minute, simmer until the sauce coats a spoon, and stir in the cheese off the heat.

7. Can I freeze au gratin potatoes?

You can, but the texture changes. Dairy sauces can turn slightly grainy after freezing and thawing.

Freeze baked portions in airtight containers for up to 2 months, thaw overnight in the fridge, and reheat covered at 350°F.

For a closer look at the base sauce, try: Bechamel Sauce Recipe

Final Thoughts

Au gratin potatoes are the kind of side dish that makes a plain dinner feel like a holiday. Once you master the roux and the 1/8-inch slice, the rest is simple.

Give this recipe a try and let me know how it turned out in the comments below. If you enjoyed it, share it with a friend who is planning a holiday menu.

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• Roasted Potatoes Recipe
• Smashed Potatoes Recipe
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• Sweet Potato Casserole Recipe
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