Leek and Ham Gratin

This gratin de poireaux au jambon, honestly, every time I make it the kitchen just smells like some cozy Paris apartment–soft buttery leeks melting into creamy béchamel, the salty comfort of good ham, and that crackle on top from a golden crust of Gruyère. It’s not showy, not fussy, but it wraps around your senses in that quiet, deeply satisfying way. The kind of warmth that slow-cooks into you.

Why You’ll Crave It

• It’s full of gentle, elegant flavors that somehow still feel indulgent–like a hug on a plate
• The textures get you every time–creamy, melty inside with that crisp-salty golden top
• Makes leeks the star, which is rare and, frankly, refreshing
• Comfort food that doesn’t feel heavy–perfect for in-between seasons
• You can prep it ahead and just pop it in the oven, which feels like a little gift to future you

The first time I made this, it was raining–soft rain, the kind you barely notice. I had forgotten to close the kitchen window, and the whole house smelled of steamed earth and melting cheese. It was perfect.

What You’ll Need

• Leeks: 500 grams, cleaned carefully and sliced into 1 cm rounds – they’re the soft, mellow base of the dish
• Ham: 200 grams, diced – something tender and salty, like a mild country ham
• Cream: 250 milliliters, full-fat is best for richness
• Milk: 100 milliliters, I use whole milk–it balances the cream without thinning
• Gruyère cheese: 150 grams grated – that nutty tang carries the whole dish
• Butter: 30 grams, for your béchamel base
• Flour: 30 grams, to make the roux–don’t skip this step
• Salt and Pepper: gently used, just enough to lift things
• Nutmeg: a whisper–really, just a pinch—but it makes a difference

Easy How-To

Clean and Prep the Leeks

This part takes a bit of patience. Leeks love to hide dirt between the layers, so slice them lengthwise first, rinse well under cool water, then slice into even little rounds. They’ll cook more evenly that way.

Blanch the Leeks

Boil a large pot of salted water, toss in the leeks, and let them soften for about 10 minutes. They should be tender but still hold their shape. Drain and let them rest a moment while you prep the sauce.

Make the Béchamel

In a saucepan, melt your butter over medium heat and whisk in the flour–keep the mix moving around the pan for about 2 minutes (you want to cook out that raw taste). Slowly whisk in the milk and cream, a bit at a time. It’ll feel thin at first, then suddenly–thick and glossy. Season with salt, pepper, and just a touch of nutmeg. It should taste quietly warming. If it tastes like nothing, add a bit more salt.

Mix Together

Toss the drained leeks and diced ham in with half the béchamel. Stir it gently so everything is coated. It’ll feel like not enough sauce at first, but once it bakes, it settles in perfectly.

Assemble the Gratin

Preheat the oven to 200°C (about 390°F). Butter a baking dish, then spread your mixture gently into it. Pour the remaining béchamel over the top. And now–the cheese. Sprinkle it generously, evenly, no skimping.

Bake It

Bake for 25–30 minutes until the top is golden, bubbling gently around the edges. You’ll want to stand by the oven. That smell deserves company.

Rest and Serve

Let it sit for 5 minutes after baking. Things settle. Flavors come together while it cools just enough to slice. Then serve–preferably with a crisp green salad and nothing else complicated.

Good to Know

• You can prep this the night before. Just assemble, cover, and pop it in the fridge. Add 10 minutes to the bake time if it’s cold when it goes in.
• If your béchamel splits or turns lumpy—don’t panic. Just whisk the life out of it, off the heat for a moment, and it’ll usually come right back.
• This dish is surprisingly kid-friendly… as long as they don’t see the leeks going in. Call it ‘cheesy ham bake’ and you’re golden.

Serving Ideas

• Pairs perfectly with a simply dressed arugula or frisée salad for balance
• Serve as a side with roast chicken or pork tenderloin for a cozy dinner
• Or eat it solo, with a spoon, from the dish, in front of the fridge (no shame)

Top Tricks

• Give the leeks a minute to drain well–too much water will thin your sauce in the oven
• Grate your cheese fresh if you can – it melts smoother and gives that perfect crust
• Use the broiler for the last 2 minutes of baking if you want a deeper, toastier top (but watch it like a hawk)

Frequently Asked Questions

Can I use frozen leeks for this recipe?

Yes, though fresh ones give better texture. Just thaw completely and press out extra liquid before mixing them in.

What can I substitute for ham?

Cooked chicken works well, especially leftover roast. Or sautéed mushrooms if you’re going vegetarian–they add great depth.

How do I store leftovers?

Cover it well and refrigerate. It keeps nicely for two, maybe three days. Reheat in the oven or microwave until warm throughout.

Can I reheat the gratin?

Yes–oven is best to keep the top crisp. About 15 minutes at 180°C (350°F). Cover loosely with foil if you’re worried about burning the top.

What type of cheese works best?

Gruyère is classic–melts beautifully and has a nutty sharpness. Comté or Emmental work too. Even a smoked cheddar adds a lovely twist.