If there’s one dish that embodies comfort, indulgence, and a touch of elegance, it’s a Savory Potato and Leek Gratin. With layers of thinly sliced potatoes, tender leeks, and creamy cheese sauce, this dish can elevate any meal. Whether served alongside roasted meats, grilled vegetables, or as a standalone vegetarian option, it’s versatile, satisfying, and irresistibly golden on top.

This recipe blends the earthy flavors of potatoes with the subtle sweetness of leeks, all enveloped in a creamy béchamel-style sauce. The gratin bakes until bubbly, golden, and lightly crisp on top, making it a true showstopper on your dinner table. It’s not just delicious—it’s also a feast for the eyes, perfect for gatherings or cozy weeknight dinners.

Why This Recipe Works

The magic of a potato and leek gratin lies in layering textures and flavors. Thinly sliced potatoes absorb the cream and cheese while baking, resulting in tender, melt-in-your-mouth layers. Leeks add a delicate oniony sweetness, balancing the richness of the sauce. Using a combination of cheeses, like Gruyère or cheddar, gives a nutty, flavorful crust. A hint of garlic, thyme, and nutmeg enhances the dish without overpowering the natural flavors.

This recipe is also forgiving. Even if you don’t slice the potatoes perfectly thin, the gratin still turns out creamy and delicious. Plus, it can be made ahead and reheated—perfect for meal prep or holiday feasts.

Ingredients

2 lbs (900g) Yukon gold or russet potatoes, thinly sliced
2 large leeks, cleaned and sliced into rings
3 tbsp unsalted butter
2 cloves garlic, minced
2 cups heavy cream
1 cup whole milk
1 tsp salt (adjust to taste)
½ tsp black pepper
¼ tsp ground nutmeg
1 ½ cups grated Gruyère cheese (or cheddar)
¼ cup grated Parmesan cheese
2 tsp fresh thyme leaves (plus extra for garnish)

Instructions

Preheat oven and prep dish
Preheat your oven to 375°F (190°C). Grease a 9×13-inch baking dish with butter and set aside.
Prepare the leeks
In a medium skillet, melt butter over medium heat. Add the leeks and sauté for 5–7 minutes until softened. Add garlic during the last minute and cook until fragrant. Remove from heat.
Prepare the cream mixture
In a saucepan, combine heavy cream, milk, salt, pepper, and nutmeg. Heat gently over medium-low heat until warm, but do not boil. Stir in 1 cup of Gruyère cheese until melted and smooth.
Layer the potatoes and leeks
Arrange a third of the potato slices in an even layer in the prepared baking dish. Top with half of the sautéed leeks and sprinkle ⅓ of the remaining Gruyère cheese. Repeat layers once more. Finish with the final layer of potatoes, remaining cheese, and Parmesan. Sprinkle thyme over the top.
Bake the gratin
Cover the dish with foil and bake for 35 minutes. Remove foil and continue baking for an additional 25–30 minutes until the top is golden brown and bubbling. Check for doneness by inserting a fork into the center; potatoes should be tender.
Rest and serve
Allow the gratin to rest for 10 minutes before serving. This helps the layers set slightly for cleaner slices. Garnish with extra fresh thyme before serving.

Tips for the Perfect Gratin

Slice potatoes evenly: A mandoline makes this effortless and ensures even cooking.
Cheese choice: Gruyère gives a classic nutty flavor, but you can use cheddar, Fontina, or a mix.
Cream consistency: For a richer gratin, increase the cream to 2 ½ cups. For a lighter version, substitute half the cream with milk.
Make ahead: Assemble the gratin a day ahead, cover tightly, and refrigerate. Bake covered at 375°F (190°C) until bubbly, about 60–70 minutes.

Variations

Herb variations: Add rosemary or sage for a more aromatic profile.
Vegetable mix-ins: Layer in thinly sliced zucchini or mushrooms for added flavor and nutrition.
Vegan option: Substitute heavy cream with coconut cream or a cashew-based cream, and use vegan cheese.

Serving Suggestions

Holiday meals: Serve alongside roasted turkey, ham, or chicken.
Weeknight dinners: Pair with a simple green salad or roasted vegetables for a cozy, balanced meal.
Vegetarian feast: Make it the centerpiece with a side of garlic green beans or steamed asparagus.

Fun Facts and Cultural Context

The word gratin comes from the French term gratter, meaning “to scrape” or “to grate,” referring to the browned crust on top.
Potato gratins have been a staple in French cuisine since the 18th century and are often served as an indulgent side dish during festive meals.
Leeks are considered a symbol of Wales and are celebrated on St. David’s Day, but their gentle flavor has made them a staple in classic French dishes like this gratin.

Why You’ll Love This Recipe

This Savory Potato and Leek Gratin combines comfort, elegance, and simplicity. Each bite offers creamy, cheesy layers with a subtle sweetness from leeks and a hint of aromatic herbs. It’s the perfect side for special occasions or just elevating your everyday dinner. The balance of textures—from tender potatoes to a golden crust—makes it irresistible.

Whether you’re a seasoned home cook or a beginner, this gratin is approachable, satisfying, and always a crowd-pleaser. Make it your next dinner centerpiece and experience the rich flavors of classic French comfort food.