Black Truffle Smoked Potatoes au Gratin

This rich, creamy, and smoky spin on the French classic Potatoes au Gratin is the ultimate indulgent side dish. With layers of tender sliced potatoes, a silky cream sauce, bold truffle seasoning, and a crispy cheese topping, this recipe elevates humble spuds into something absolutely unforgettable.

Black Truffle Smoked Potatoes au Gratin

Potatoes Gratin (or Gratin Dauphinois if you want to impress your dinner guests) was one of my childhood favorites, second only to scalloped potatoes. But this version, loaded with smoky cream, truffle seasoning, and cheese, takes things to a whole new level.

Using a smoker to cook this classic dish gives it an incredible depth of flavor—and that crispy cheese crust? Absolute magic. Don’t let the fancy name intimidate you—it’s actually super easy and budget-friendly to make.

How to Make Black Truffle Smoked Potatoes au Gratin

Preparation

Start by preheating your smoker to 350°F. While the smoker heats up, prepare your potatoes and onions. You’ll want to slice both very thin—about 1/16 of an inch thick. A mandolin slicer works best for uniformity, but a sharp knife and some patience will do the trick. Uniform thickness ensures that everything cooks evenly and the final texture is silky smooth with no raw or overcooked pieces.

I personally like using small white creamer potatoes because they’re already washed, have a creamy texture, and their small size makes slicing a bit easier. Once sliced, do the same with your onions. These add a subtle sweetness and depth to the dish.

Set the sliced veggies aside and get your roasting pan ready. This should be a smoker-safe dish like cast iron or a disposable foil roasting pan if you’re cooking for a crowd or bringing it to a potluck.

Mix the Ingredients Together in the Roasting Pan

Into the roasting pan, add all your thinly sliced potatoes and onions. Pour in the heavy cream and toss in chunks of softened butter to help bind and flavor everything. Now sprinkle in your black truffle seasoning. This is where the magic starts—earthy, savory, and aromatic, the truffle transforms this dish from comfort food to gourmet.

Next, add about 1 pound of shredded cheese—go for something with bold flavor that also melts well like sharp cheddar, gouda, gruyère, or marble. Give everything a good mix, making sure every slice is coated in the creamy, cheesy goodness. Be sure to reserve about ½ pound of cheese for the final topping.

Roasting the Potatoes on the Smoker

Place the pan on the preheated smoker at 350°F and let it cook uncovered for 1 hour. During this time, the potatoes will soften, the onions will melt into the cream, and the entire mixture will start to bubble. You’ll notice the edges begin to brown slightly—this is a good sign.

After an hour, use a fork or thin knife to test for doneness. The potatoes should be tender but not falling apart. This is also a great moment to taste test for seasoning. Potatoes can absorb a lot of salt, so if it feels under-seasoned, sprinkle a little more truffle seasoning or salt and stir gently without breaking the layers too much.

Add the Gratin (Crispy Cheese Topping)

Once your potatoes are cooked through and the cream is bubbling, it’s time to add the “gratin” part of this dish—the crispy cheese crust that gives it that golden top layer.

Sprinkle the remaining ½ pound of shredded cheese evenly across the surface. You want a full, cheesy crust that will brown up beautifully in the final cook.

Now crank up the smoker’s temperature to 500°F. This high heat will help crisp the cheese and give the top that signature gratin crunch. Let it cook for about 15 to 20 more minutes, or until the cheese is golden, bubbly, and developing a crust. Keep an eye on it—cheese can go from perfect to burnt quickly at this temperature.

Serving the Dish

Once the gratin crust is crisp and golden, remove the pan from the smoker using heatproof gloves or a thick towel. This dish is hot and heavy—literally and flavor-wise—so be careful.

Serve it directly from the roasting dish so you don’t disturb that gorgeous cheese layer. I recommend scooping with a large spoon to get all the layers intact—from the creamy base to the crispy top.

Best Beer to Pair With Black Truffle Potatoes au Gratin

Belgian Dubbel

Malty, rich, and slightly sweet—this beer mirrors the creamy comfort of the gratin without overwhelming the truffle.

Brown Ale

Toasty and mellow, brown ales bring nutty notes that pair beautifully with smoked cheese and buttery potatoes.

Dry Apple Cider

A sharp, crisp cider cuts through the richness and adds a fruity contrast to the truffle and cheese.

Black Truffle Smoked Potatoes au Gratin FAQs