Name: Leek Gratin Recipe
Prep time: 15 min
Cook time: 35 min
Total time: 50 min
Cuisine: French
Ingredients: 4 large leeks (white and light green parts only, cleaned and sliced lengthwise); 2 tablespoons unsalted butter; 1 tablespoon all-purpose flour; 1 cup heavy cream; 1/2 cup whole milk; 1/2 teaspoon salt; 1/4 teaspoon black pepper; 1/4 teaspoon nutmeg; 1/2 cup grated Gruyère cheese; 1/4 cup grated Parmesan cheese; 1/4 cup breadcrumbs (optional); Chopped fresh thyme or parsley

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If you’re looking for a side dish that’s as elegant as it is scrumptious, let me introduce you to Leek Gratin! This dreamy French-inspired bake wraps sweet, mellow leeks in a lusciously creamy sauce before finishing with golden, bubbling cheese on top. It’s velvety, comforting, and impossibly easy to fall in love with, whether you serve it at a festive gathering or alongside a simple roast chicken. Leek Gratin transforms humble ingredients into something worthy of a weekend treat, and trust me—everyone at your table will ask for seconds.

Ingredients You’ll Need

This Leek Gratin proves that a few carefully chosen ingredients can create major magic. Each one is integral—bringing out the best texture, flavor, or color in this cozy classic. Here’s what you need and why you need it:

Leeks: Their soft, slightly sweet flavor forms the heart of the gratin—make sure to clean them thoroughly!
Unsalted butter: This gives richness and helps create the classic roux for your creamy sauce.
All-purpose flour: Just enough to gently thicken the sauce without making it heavy.
Heavy cream: For that signature lush, velvety sauce that coats each leek beautifully.
Whole milk: Lightens the sauce just a touch—balancing richness and pourability.
Salt: Essential to season every layer and bring out the complexity of the leeks.
Black pepper: A little pepper wakes up the creamy flavors with a hint of warmth.
Nutmeg: This classic gratin spice adds subtle depth and a whiff of nutty aroma.
Gruyère cheese: Melts into irresistible strings and gives that unmistakable French gratin flavor.
Parmesan cheese: Boosts umami and brings a lovely, toasty edge to the top.
Breadcrumbs (optional): For those who love a little crunch on top—totally optional but always appreciated.
Chopped fresh thyme or parsley: Adds color and a bright, herbal note just before serving.

How to Make Leek Gratin

Step 1: Prepare the Leeks and Baking Dish

Start by preheating your oven to 375°F (190°C) and giving your baking dish a quick brush of butter—it’ll help prevent any sticking and add extra flavor. Arrange the leeks, sliced lengthwise, cut side up in the dish. This not only looks beautiful but allows every bit of creamy sauce and melted cheese to seep into the layers.

Step 2: Make the Creamy Sauce

Melt the butter in a saucepan over medium heat, then sprinkle in the flour. Whisk the mixture constantly for a minute or two; you want it just golden and fragrant, not deeply browned. Gradually pour in the heavy cream and milk, whisking all the while to keep things silky smooth. Add salt, pepper, and that hint of nutmeg, then let it simmer for a few minutes until gently thickened. You’re aiming for a pourable custard consistency.

Step 3: Assemble the Gratin

Pour the warm cream sauce over the prepared leeks, making sure every piece is lightly coated. Sprinkle Gruyère and Parmesan evenly over the top, then scatter breadcrumbs over everything for a little extra crunch if you love that golden crust.

Step 4: Bake Until Golden

Cover the dish loosely with foil and slide it into the oven. After 20 minutes, remove the foil and let the gratin continue baking until the top is golden, bubbly, and absolutely mouthwatering—about 15 to 20 more minutes. Let it rest for five minutes once out of the oven so it sets enough for perfect servings.

How to Serve Leek Gratin

Garnishes

Just before bringing your Leek Gratin to the table, shower the top with fresh thyme or chopped parsley. The green pops against the cheesy gold and adds an herby freshness that brightens every bite.

Side Dishes

This dish is perfectly content as a show-stopping side. Pair Leek Gratin with roasted or grilled meats, a tender roast chicken, or a holiday ham. It also plays beautifully alongside lighter salads or simple French bread, soaking up every last drop of sauce.

Creative Ways to Present

Want to dazzle guests? Try baking the Leek Gratin in individual ramekins for a dinner party, or spoon it onto slices of crusty baguette for a rustic, cheesy appetizer. For brunch, serve a scoop alongside softly poached eggs—pure luxury!

Make Ahead and Storage

Storing Leftovers

Got leftovers? Store any remaining Leek Gratin in an airtight container in the fridge. It’ll keep beautifully for up to three days—reheat and it’s just as comforting as day one.

Freezing

Surprisingly, Leek Gratin freezes quite well! Let it cool completely before wrapping tightly. Freeze for up to two months; just know you may lose a bit of that crunch on top, but the creamy flavor remains strong.

Reheating

To reheat, cover the dish with foil and warm in a 350°F (175°C) oven until heated through. For microwave reheating, use short intervals so the sauce doesn’t separate, and enjoy piping hot.

FAQs

Can I use a different cheese in my Leek Gratin?

Absolutely! While Gruyère and Parmesan are classic, feel free to try Swiss, Emmental, or even a bit of sharp cheddar for a different twist. Each cheese lends its unique character—get creative!

Is it possible to make Leek Gratin gluten-free?

Yes, simply substitute a gluten-free all-purpose flour blend for the regular flour, and use gluten-free breadcrumbs or omit them entirely for the topping. The results will still be creamy and luscious.

Should I pre-cook the leeks before baking?

You certainly can! Sautéing them in a bit of butter first adds extra richness and helps ensure they’re meltingly soft by the time your gratin is done. It’s a wonderful option if you like your leeks ultra-tender.

Can I prepare Leek Gratin in advance?

Definitely. Assemble everything a few hours ahead of time, cover, and refrigerate. When you’re ready, bake it straight from the fridge (add a couple of extra minutes to the baking time) for fuss-free entertaining.

What’s the best way to clean leeks?

Leeks often hide grit between their layers. Slice them lengthwise and rinse under running water, fanning out the layers to ensure all dirt is removed. Dry well before using for the best texture in your Leek Gratin.

Final Thoughts

Once you make Leek Gratin, you’ll wonder how you ever enjoyed leeks any other way. It’s a recipe that feels fancy but welcomes you like an old friend at the table—a little French flair with every creamy, bubbling bite. Give it a try and watch it disappear faster than you thought possible!

Leek Gratin Recipe

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4.5 from 19 reviews

Author: admin
Total Time: 50 minutes
Yield: 4 servings 1x
Diet: Vegetarian

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Description

Indulge in the creamy and flavorful delight of Leek Gratin, a classic French side dish that combines tender leeks with a rich, cheesy sauce baked to perfection. This recipe is sure to elevate any meal with its decadent taste and elegant presentation.

Ingredients

Scale

Leeks:

4 large leeks (white and light green parts only, cleaned and sliced lengthwise)

Cheese Sauce:

2 tablespoons unsalted butter
1 tablespoon all-purpose flour
1 cup heavy cream
1/2 cup whole milk
1/2 teaspoon salt
1/4 teaspoon black pepper
1/4 teaspoon nutmeg
1/2 cup grated Gruyère cheese
1/4 cup grated Parmesan cheese

Topping:

1/4 cup breadcrumbs (optional)

Garnish:

Chopped fresh thyme or parsley

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Instructions

Preheat the oven: Preheat the oven to 375°F (190°C) and butter a medium baking dish.
Prepare leeks: Arrange cleaned, halved leeks cut side up in the dish.
Make sauce: Melt butter in a saucepan, whisk in flour to make a roux, then add cream, milk, salt, pepper, and nutmeg. Simmer until slightly thickened.
Assemble: Pour cream mixture over leeks. Sprinkle Gruyère and Parmesan on top. Add breadcrumbs if desired.
Bake: Cover with foil and bake for 20 minutes. Remove foil and bake for 15–20 more minutes until golden and bubbly.
Serve: Let rest for 5 minutes before garnishing with fresh thyme or parsley.