Thinly sliced potatoes layered with cream and cheese — potatoes au gratin are a classic comfort food that never fails to delight.
When I was growing up, scalloped potatoes au gratin came from a box and practically glowed orange. As a kid, I didn’t think twice about the dehydrated potatoes or powdered cheese — I just knew I loved them. I still see those boxed versions at the grocery store, and I’ll admit there’s a little nostalgia there. But once you make real potatoes au gratin from scratch, there’s no going back.
This version is everything the boxed mix was trying to be: creamy, rich, deeply savory, and layered with real flavor.
What are potatoes au gratin?
Potatoes au gratin are thinly sliced potatoes layered with cream and cheese, then baked until the potatoes are perfectly tender and the top is golden brown and bubbling.
The dish is often confused with scalloped potatoes, which traditionally do not include cheese. In potatoes au gratin, cheese is part of what gives the dish its structure and richness.
Potatoes au gratin are commonly served for holidays or gatherings alongside roasted beef, baked ham, roast chicken, or rack of lamb. It’s a reliable side dish that feels both classic and special.
Why This Potatoes Au Gratin Recipe Works
Russet potatoes create the right texture
The type of potato matters. Russet potatoes contain enough starch to help thicken the cream as the dish bakes, creating layers that are tender but still structured. Other varieties tended to become either too firm or overly soft.
Thin slices cook evenly
After testing different thicknesses, 1/8-inch slices produce the most consistent results. This thickness allows the potatoes to cook through evenly while maintaining distinct layers. A mandoline makes this step especially easy.
Infusing the cream builds flavor
Many recipes rely only on cream and potatoes, but gently warming the cream with garlic and thyme adds subtle depth without overpowering the dish. This small step creates a more balanced and flavorful sauce.
Cheese is what makes this au gratin
Traditional scalloped potatoes are made without cheese, but potatoes au gratin include cheese as part of the structure of the dish. A modest amount of cheddar and parmesan adds both nuttiness and creaminess without making the dish heavy.
Covered baking prevents uneven cooking
Covering the dish for part of the baking time allows the potatoes to gently braise in the cream. This helps the layers cook evenly before the top browns, preventing the surface from drying out too quickly.
Resting helps the layers set
Allowing the dish to rest for 10–15 minutes after baking helps the cream thicken slightly so the layers hold together when served, while still remaining creamy.
What is the difference between scalloped potatoes and potatoes au gratin?
Scalloped potatoes are traditionally made with thinly sliced potatoes baked in a cream or milk-based sauce without cheese. Potatoes au gratin include cheese layered between the potatoes, creating a richer flavor and slightly firmer texture. Many modern recipes combine elements of both, which is why the terms are sometimes used interchangeably.
What are the best potatoes for potatoes au gratin?
Russet potatoes work best because their higher starch content helps thicken the cream sauce as the dish bakes, creating tender layers that hold together well.
Can potatoes au gratin be made ahead of time?
Yes, Absolutely. The dish can be assembled up to one day in advance, covered, and refrigerated before baking. Take it out of the refrigerator 30 minutes before baking to take the hard chill off and add a few extra minutes to the baking time if ingredients are cold.
Why did my potatoes au gratin turn watery?
Watery potatoes au gratin are often caused by using low-starch potatoes or not allowing enough time for the cream to thicken and set while baking and resting.
How long should potatoes au gratin rest before serving?
Allow the dish to rest for 10–15 minutes after baking. This helps the cream set slightly so the layers hold together while remaining creamy and to cool off. This dish stays retains heat for a very long time.
Helpful Tips:
- A 9″ oval or square baking dish is the perfect size.
- Make ahead for easy serving.
Potatoes Au Gratin (Scalloped Potatoes with Cheese)
Ingredients
- 2 cups heavy cream
- 3 bay leaves
- 1 tbsp fresh thyme leaves
- 2 garlic cloves minced
- 1/4 teaspoon freshly grated nutmeg
- 1/2 teaspoon kosher salt
- 1/4 teaspoon fresh black pepper
- unsalted butter
- 2 pounds russet potatoes peeled and cut into 1/8-inch-thick slices
- .5 cup shredded sharp cheddar cheese (or a blend of cheddar, gruyere, etc)
- .5 cup freshly grated parmesan cheese
Instructions
- Preheat the oven to 400° F.
- Lightly butter a casserole dish and set aside.
- In a saucepan, heat up the cream gently with the bay leaves, thyme, garlic, nutmeg and some salt and pepper. Do not boil- just heat. Once the cream is headed, use a slotted spoon to remove the bay leaves from the cream.
- Meanwhile, use a mandolin to slice the peeled potatoes into 1/8" rounds.
- Pour the heated cream into a large bowl with the potato slices. Mix gently to coat the potatoes. (hands works well here!)
- Add a few tablespoons of cream to the bottom of the cassarole dish. Add a layer of potatoes, overlapping them slightly. Add a light layer of the shredded cheese. (Do not cover potatoes completely with cheese or it will be oily- Just a gentle sprinkle of cheese on each layer will do.) Spoon a bit of the cream over potatoes and repeat – layering potatoes, cheeses and cream, ending with pouring any remaining cream over the top. Top with a final light layer of cheese blend.
- Cover the dish with aluminum foil. Use a knife to make vent holes holes in the foil for the steam to escape. Bake for about 40 minutes and then uncover fr the final 10-20 minutes. (Broil on low for 2-4 minutes if necessary for desired browning) Rest covered for 15 minutes before serving- it will be very hot.
