This potatoes au gratin recipe strikes that rare balance: decadent enough for a celebratory dinner, simple enough for a cozy weeknight. With thinly sliced russet potatoes soaked in a fragrant cream blended with garlic and thyme, then topped with a crust of Gruyère and Parmesan, this dish delivers rich, layered comfort in every mouthful. It’s the kind of side dish that tastes like home but elevated.
Whether you call it au gratin potatoes, potato gra-TAN, scalloped potatoes, or simply that cheesy potato dish, this version is designed to be reliably comforting, crowd-pleasing, and beautifully satisfying.
Tips & FAQs for the best potatoes au gratin
- What kind of potatoes should I use?
Choose starchy potatoes, such as russets or Idaho potatoes. Their higher starch content helps thicken the creamy sauce (which is why you also shouldn’t rinse them after slicing). You could also mix in Yukon golds if you’d like to use a variety. These kinds of potatoes retain their shape when thinly sliced, preventing a mushy result. - How should I slice the potatoes? Should I peel them first?
Use a mandoline or a very sharp knife to cut the potatoes into thin, even slices. Uniform slices help ensure the gratin cooks evenly and prevent undercooked potatoes from hiding in the center. Whether or not you peel them first is entirely up to you. We love the look of a rustic gratin with the skins on; if you prefer a more elegant look, put your peeler to work. - Do I have to simmer the cream on low?
Heating the cream gently helps prevent it from breaking, in turn resulting in a smooth, not watery sauce. It it boils too hard or over-reduces, the texture will suffer. - How do I make the top crispier?
First, don’t skip the instruction to broil at the end of the recipe. This browns the crown of cheese and crisps the edges. But, if you want an even crunchier experience, you can toss the cheese with breadcrumbs (preferably panko; about ¼ cup) before topping the gratin. - What’s the difference between potatoes au gratin and scalloped potatoes?
Gratins, which can be made with various ingredients (not just potatoes), tend to be the richer of the two. Distinctly, it’s the cheese that differentiates them. Scalloped potatoes, in their classic form, skip the cheese and are baked in a simple creamy or béchamel-style sauce. Many American recipes have conflated the terms, however, and you’ll see plenty of recipes with titles such as “cheesy scalloped potatoes.”
What you’ll need
3-Qt. Baking Dish
$17 At Amazon
Kyocera Ceramic Mandoline Slicer
$25 At Amazon
Small Saucepan
$155 At Amazon
Immersion Blender
$100 At Amazon
Heavy-Duty Aluminum Foil
$12 At Target
Recipe information
Total Time
2 hours
Yield
12 Servings
Ingredients
5
1
2
2½
1
1
1
4
3
1
Need to make a substitution?
Preparation
Step 1
Preheat oven to 325°. Cut 1 garlic clove in half and rub the cut sides all over the inside of a 3-qt. shallow baking dish. Smear 1 Tbsp. unsalted butter, room temperature, all over inside of dish. Bring 2 medium shallots, quartered through root ends, 2½ cups heavy cream, 1 Tbsp. Diamond Crystal or 1¾ tsp. Morton kosher salt, 1 tsp. freshly ground black pepper, 1 Tbsp. thyme leaves, and remaining 4 garlic cloves to a simmer in a small saucepan over low heat; cook until shallots and garlic are very soft, 15–20 minutes. Let cool slightly. Transfer to a blender; blend until smooth.
Step 2
Arrange 4 lb. russet potatoes, scrubbed, very thinly sliced on a mandoline, in prepared dish, fanning out a handful at a time and placing in dish at an angle (this ensures every scoop will have tender potatoes from the bottom and crispy edges from the top). Shingle sliced potatoes as you work until bottom of dish is covered. Tuck smaller slices into any gaps to fill. Pour cream mixture over potatoes and cover dish tightly with aluminum foil. Bake potatoes until tender and creamy, 60–75 minutes. Let cool.
Step 3
Place rack in highest position; heat broiler. Remove foil and top potatoes with 3 oz. Gruyère, finely grated, and 1 oz. Parmesan, finely grated. Broil until cheese is bubbling and top of gratin is golden brown, 5–10 minutes. Serve topped with more thyme leaves.
Do Ahead: Gratin can be baked 1 day ahead. Cover and refrigerate. Bring to room temperature before broiling.
Editor’s note: This potato gratin recipe was first printed in October 2015 and has been updated for style. Head this way for more of our favorite Christmas dinner ideas →