How To Make Classic Potatoes Au Gratin Recipe

I perfected my Creamy Baked Potato Casserole and finally learned the sneaky little step that makes every slice impossible to ignore.

I’ve made a ton of potato dishes but Potatoes au Gratin still manages to surprise me, it looks fancy but often isn’t. Thin rounds of Yukon Gold potatoes and nutty Gruyere cheese melt together into a Creamy Baked Potato Casserole that somehow feels both elegant and totally approachable.

There’s this little thrill when you lift the top and steam unfurls, you pause cause you weren’t expecting that level of richness from such simple things. If you’ve been hunting the Best Potatoes Au Gratin Recipe you’ll want to stick around, I guarantee it will change the way you think about potato sides.

Ingredients

• Potatoes give creamy starch and body, decent fiber and potassium, slightly sweet.
• Heavy cream makes the dish rich and silky, mostly fat, adds luxurious mouthfeel.
• Whole milk lightens richness, provides protein and calcium, adds mild dairy flavor.
• Gruyere melts beautifully, nutty savory flavor, good protein and calcium, not too sharp.
• Parmesan gives salty umami punch, finely grated for crust, concentrated flavor boost.
• Garlic adds aromatic bite, small amounts brighten richness, contains antioxidants.
• Butter aids browning and flavor, adds saturated fat, helps everything feel rounded.
• Chives lend fresh oniony brightness, garnish that cuts richness without adding calories.

Ingredient Quantities

• about 2 to 2 1/2 pounds Yukon Gold or Russet potatoes peeled and thinly sliced 1/8 inch thick
• 2 cups heavy cream
• 1 cup whole milk
• 2 tablespoons unsalted butter plus a little extra for greasing the dish
• 2 cloves garlic minced
• 8 ounces Gruyere cheese grated about 2 cups
• 1/2 cup finely grated Parmesan cheese
• 1 teaspoon kosher salt
• 1/2 teaspoon freshly ground black pepper
• pinch of freshly grated nutmeg
• 2 teaspoons fresh thyme leaves or 1 teaspoon dried thyme optional
• 2 tablespoons chopped fresh chives optional

How to Make this

1. Preheat oven to 375°F and butter a 9×13 inch baking dish with a little of the extra butter; set aside. If you have a mandoline, slice the potatoes 1/8 inch thick with care, otherwise use a sharp knife. Use about 2 to 2 1/2 pounds Yukon Gold or Russet, peeled.

2. Pat the slices dry on a clean towel or paper towels for a minute to remove excess surface moisture; this helps the sauce cling better. Don’t worry if they aren’t perfect, some overlap is fine.

3. In a medium saucepan melt 2 tablespoons unsalted butter over medium heat, add the 2 cloves minced garlic and sauté 30 to 45 seconds until fragrant but not browned. Pour in 2 cups heavy cream and 1 cup whole milk, warm gently until small bubbles form at the edge, stirring so it does not scorch.

4. Season the warmed cream with 1 teaspoon kosher salt, 1/2 teaspoon freshly ground black pepper, a pinch of freshly grated nutmeg, and 2 teaspoons fresh thyme leaves or 1 teaspoon dried thyme if using. Taste and adjust lightly, then remove from heat.

5. Stir about 1 1/2 cups grated Gruyere and all of the 1/2 cup finely grated Parmesan into the hot cream until mostly melted; reserve about 1/2 cup Gruyere for the top. This makes the sauce extra cheesy and helps it set up.

6. Arrange a single even layer of potato slices in the buttered dish, overlapping slightly, then sprinkle a little of the reserved Gruyere and a few thyme leaves if you like. Repeat to make 2 to 3 layers depending on dish depth, finishing with a layer of potatoes.

7. Pour the hot cream and cheese mixture evenly over the potatoes, pressing down gently so the liquid sinks between slices. Scatter the remaining reserved Gruyere over the top.

8. Cover tightly with foil and bake 45 minutes. Then remove foil and bake another 15 to 20 minutes until top is bubbling and golden and a knife slides easily into the center. If it browns too fast, tent with foil.

9. Let the gratin rest 10 to 15 minutes so it sets, then sprinkle 2 tablespoons chopped fresh chives over the top if using. Serve warm as a rich, creamy side — and yes, leftovers reheat great.

Equipment Needed

1. 9×13 inch baking dish, buttered a little
2. Mandoline slicer or a sharp chef’s knife (if you dont have a mandoline)
3. Vegetable peeler
4. Cutting board
5. Medium saucepan
6. Measuring cups and spoons
7. Box grater or microplane for Gruyere and Parmesan
8. Kitchen towels or paper towels to pat the potatoes dry
9. Aluminum foil and oven mitts for baking and safety

FAQ

How To Make Classic Potatoes Au Gratin Recipe Substitutions and Variations

How To Make Classic Potatoes Au Gratin

Intro
Creamy, cheesy, a little bit crunchy on top and totally comforting. This is the classic potatoes au gratin everyone fights over at holidays. It looks fancy but honestly it’s super simple if you slice the potatoes thin and let the cream do the work. You’ll wanna make this again and again.

Ingredients
– about 2 to 2 1/2 pounds Yukon Gold or Russet potatoes, peeled and thinly sliced 1/8 inch thick
– 2 cups heavy cream
– 1 cup whole milk
– 2 tablespoons unsalted butter plus a little extra for greasing the dish
– 2 cloves garlic, minced
– 8 ounces Gruyere cheese, grated (about 2 cups)
– 1/2 cup finely grated Parmesan cheese
– 1 teaspoon kosher salt
– 1/2 teaspoon freshly ground black pepper
– pinch of freshly grated nutmeg
– 2 teaspoons fresh thyme leaves or 1 teaspoon dried thyme optional
– 2 tablespoons chopped fresh chives optional

Equipment & quick tips
– Mandoline or sharp knife for even slices — even thickness = even cooking.
– 9×13 inch baking dish or a 2 to 3-quart gratin dish.
– Warm the cream mixture before pouring it over the potatoes so the dish starts cooking faster.
– Let it rest 10 minutes after baking so it sets, don’t try to shovel it out right away.

Instructions
1. Preheat oven to 375 F and butter your baking dish well.
2. Melt the 2 tablespoons butter in a medium saucepan over medium heat. Add the minced garlic and cook 30 seconds until fragrant, dont let it brown.
3. Add the heavy cream and whole milk, warm until just starting to steam but not boiling. Stir in salt, pepper, nutmeg and thyme. Taste and adjust seasoning.
4. Arrange a single layer of potato slices in the bottom of the dish, slightly overlapping. Sprinkle a little Gruyere and a little Parmesan over that first layer.
5. Pour about a quarter of the warm cream mixture over the cheese and potatoes so it’s barely covered. Repeat with another layer of potatoes, cheese, cream. Finish with a top layer of potatoes and the remaining cheeses.
6. Cover the dish tightly with foil and bake for 40 to 50 minutes. Then remove foil and bake another 20 to 25 minutes until the top is golden brown and the potatoes are tender when pierced with a knife.
7. Let rest 10 to 15 minutes so the gratin firms up, then sprinkle chopped chives on top if using and serve warm.

Serving & storage
Goes great with roasted meats, a simple green salad or steamed greens. Leftovers keep in the fridge for 3 to 4 days, reheat covered at 350 F until warmed through.

Substitutions

• Potatoes: use red new potatoes or fingerlings for a waxier texture that holds its shape better; you may need to reduce baking time slightly or slice a touch thinner.
• Heavy cream + whole milk: swap for 2 cups half-and-half for a lighter version, or use 1 can evaporated milk plus 1 cup regular milk in a pinch.
• Gruyere cheese: substitute Emmental, Comte, or a good melting Swiss; sharp cheddar works too but will give a stronger tang and a bit more oil.
• Parmesan cheese: use Pecorino Romano or aged Asiago for similar salty, nutty flavors.

Pro Tips

Pro tips:

– Slice even and thin, and remove starch. If you can, run the slices in cold water for a minute, then lay them out and pat completely dry. Uneven or wet slices make the sauce slide off and you’ll end up with gummy spots. If you use a mandoline, be careful — i’ve nicked myself before so use a guard or a cut-proof glove.

– Warm and taste the cream slowly, don’t let it boil. Bring the cream-garlic gently to tiny bubbles at the edge, take off the heat, then stir in most of the cheese so it melts smooth. If the sauce feels too loose, give it a minute on very low to reduce a bit, but don’t overheat or the dairy will break.

– Season between layers and don’t pack it too tight. Sprinkle a little salt and pepper (and thyme if you like) as you layer so every bite is seasoned. But leave a little space for the sauce to seep between slices, otherwise the center can stay undercooked or dry out.

– Rest and finish thoughtfully. Let the gratin sit 10 to 15 minutes after it comes out so it firms up and slices cleanly. If you want a toastier top, broil for 1 to 2 minutes at the end while watching it like a hawk, or tent with foil if it’s browning too fast during baking.