Name: Broccoli Gratin With Creamy Béchamel and Cheese (Oven-Baked)
Prep time: 10 min
Cook time: 20 min
Ingredients: 2.2 lb broccoli florets (about 1 kg broccoli, trimmed); 16 cups water; 2 1/2 tbsp fine salt; 6 tbsp unsalted butter (or 6 tbsp neutral oil); 6 tbsp all-purpose flour; 4 cups whole milk; 2 tsp fine salt; 1 tsp black pepper; Pinch of nutmeg (optional); 14 oz shredded cheese (about 400 g)

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Broccoli gratin is a baked dish made with blanched broccoli, a thick béchamel sauce, and a generous layer of cheese browned in the oven. What makes this version different is that the sauce is calibrated to stay creamy (not runny) and the broccoli is cooked quickly so it keeps a pleasant bite. It’s the kind of recipe you make for an easy weeknight dinner, a cozy weekend meal, or a make-ahead side dish anytime of year.

If you like comfort food that feels classic but still practical, this is a reliable one: simple ingredients, straightforward technique, and a result that works whether you’re cooking in Canada in the middle of winter or grilling steaks in the U.S. in the summer and want a warm, cheesy side.

Why this broccoli gratin works year-round

Broccoli is easy to find in every season, and a gratin is the type of dish that fits both cozy and fresh menus. In colder months, it’s a hearty, warming side alongside roasts and braises. In warmer months, it’s still great as a meal prep component—make it once, reheat portions, and pair it with salads or grilled proteins. Because this recipe uses a properly thick béchamel, it reheats better than many broccoli casserole recipes that depend on thinner sauces.

If you’re building a broader weeknight routine, you can also keep this gratin in the same “simple base technique” family as a good béchamel. If you want a dedicated guide, bookmark Béchamel sauce (foolproof methods) for the core technique.

Ingredient notes

A broccoli gratin is deceptively simple. The difference between “perfect” and “soupy” comes down to two things:

Broccoli cooking and draining
You want broccoli that’s tender-crisp, then drained thoroughly so steam doesn’t dilute the sauce.
A béchamel that’s thick enough to cling
The version from the transcript was a bit light on thickener for 1 litre of milk. Here, the roux is balanced so the sauce stays creamy and stable in the oven.

For a similar comfort-food vibe in a different direction, Easy traditional tartiflette recipe with reblochon or budget cheese (French Alpine comfort food) is another cheesy bake worth keeping in rotation.

Ingredients

Broccoli

2.2 lb broccoli florets (about 1 kg broccoli, trimmed)
16 cups water (about 4 L)
2 1/2 tbsp fine salt (for the boiling water)

Béchamel

6 tbsp unsalted butter (or 6 tbsp neutral oil)
6 tbsp all-purpose flour
4 cups whole milk (1 litre)
2 tsp fine salt (start with less if your cheese is salty)
1 tsp black pepper
Pinch of nutmeg (optional but classic)

Cheese topping

14 oz shredded cheese (about 400 g), such as mozzarella + sharp cheddar, or mozzarella + gruyère

Equipment

Large pot for boiling
Colander
Saucepan for béchamel
Whisk
9×13-inch baking dish (or similar)

Step-by-step instructions

1) Prep the broccoli

Cut the broccoli into evenly sized florets. If you have thick stems, peel them and slice them thinly—stems are delicious in gratins, but they need a little extra attention to cook evenly.

Bring 16 cups of water to a boil in a large pot and season it with the salt. The salted water matters: it seasons the broccoli from the inside instead of relying only on the sauce later.

2) Blanch quickly

Add the broccoli to the boiling water. When the water returns to a boil, cook for 3 minutes. You want the broccoli bright green and still firm.

Drain immediately in a colander. Don’t rinse under cold water. Instead, let it sit and steam-dry for 5–10 minutes. This step is one of the biggest keys to avoiding a watery gratin.

3) Make the béchamel

In a saucepan over medium heat, melt the butter. Add the flour and whisk continuously to form a roux. Cook for 1–2 minutes, long enough to remove the raw flour smell, but not so long that it browns.

Warm the milk (it can be hot or just very warm; either works). Add it gradually to the roux while whisking so the sauce stays smooth. Once all the milk is in, keep whisking until the béchamel thickens. When it starts to bubble, let it simmer for 1 minute to fully set the starch.

Season with salt, pepper, and nutmeg (optional). Taste and adjust. The béchamel should coat the back of a spoon and feel creamy, not thin.

If you want another comfort-food chicken dish with a creamy sauce profile, Marry Me Chicken (creamy recipe) is a good reference point for “rich but practical” weeknight cooking.

4) Assemble the gratin

Preheat the oven to 400°F.

Spread the drained broccoli in a baking dish. Pour the béchamel evenly over the broccoli, then gently toss or fold with a spoon to coat.

Sprinkle the shredded cheese over the top in an even layer. A mix works well: mozzarella for melt + a sharper cheese for flavor.

5) Bake until golden and bubbling

Bake on the middle rack for 12–18 minutes, or until the sauce is bubbling at the edges and the cheese is deeply melted and lightly browned.

If you want a more aggressive golden top, broil for 1–2 minutes at the end—watch closely so it doesn’t burn.

6) Rest, then serve

Let the gratin rest for 5 minutes before serving. This allows the sauce to settle so it holds together better.

How to keep it from turning watery

Don’t overcook the broccoli. Overcooked broccoli releases more water.
Steam-dry after draining. This is non-negotiable if you want clean slices.
Use a thicker béchamel. The corrected roux ratio is what makes this recipe dependable.
Avoid low-fat milk. Whole milk holds better in a baked sauce.

If you’re serving this with a steak night, a bold sauce pairing can be fun—try Spicy mayo (ready in 1 minute) on the side for a punchy dip for roasted potatoes or veggies.

How this recipe is different from similar dishes on the site

This is a vegetable-forward gratin with a classic béchamel base and a simple cheese top—built for clean texture, not a heavy casserole. It’s not a creamy chicken dinner, not a potato gratin, and not a cheese-and-bacon mountain bake. Think: “easy comfort side that still feels precise.”

If you’re looking for the more alpine, ultra-hearty direction, Easy traditional tartiflette recipe is the opposite end of the spectrum.

And if you want a full baked pasta comfort dish, Spaghetti with meat sauce is a different weeknight lane entirely, but it pairs well with a broccoli side like this.

Nutrition

This broccoli gratin sits in the “hearty comfort food” category, but it still brings real balance. Broccoli adds fiber and a fresh vegetal base, while the béchamel and cheese add richness and a satisfying bite. If you want it lighter, you can reduce the cheese slightly or use part-skim mozzarella, but the richest, most stable texture comes from a proper béchamel and enough cheese to brown well.

Substitutions

Cheese swaps

Mozzarella + sharp cheddar: classic, melty, flavorful
Gruyère or Swiss: more nutty, more “French gratin” character
Parmesan: mix a little into the topping for extra punch (don’t rely on it alone)

Milk swaps

2% milk works, but the sauce will be slightly less rich.
Lactose-free whole milk works well.

Butter vs oil

Butter gives the best flavor. Neutral oil works if needed, but use the same volume and cook the roux carefully.

Add-ins (optional)

A pinch of chili flakes
A spoon of Dijon in the béchamel
A small handful of chopped herbs

For a different flavor direction with heat, you can explore a harissa lane using Easy homemade sweet and sour sauce as a reference for balancing sweet/acid—different dish, same idea of building a sauce that holds.

FAQ

Can I use frozen broccoli?

Yes. Thaw fully and drain very well, then pat dry. Frozen broccoli carries extra moisture, so the steam-dry step matters even more.

Can I make it ahead?

Yes. Assemble fully, cover, and refrigerate up to 24 hours. Bake straight from the fridge—add a few extra minutes until bubbling.

How do I reheat leftovers?

Reheat in a 350°F oven until hot. Microwave works, but the top will soften. Oven reheating preserves the gratin texture.

Why did my gratin turn watery?

Usually one of these: broccoli overcooked, broccoli not drained long enough, béchamel too thin, or dish covered while hot (trapping steam).

Can I double it?

Yes. Use a larger baking dish or two dishes. Don’t crowd too thick or it takes longer to bubble and brown.

What to serve with / Suggested posts

For a full comfort-food menu:

For a cozy French-style dinner:

For a complete comfort spread:

Broccoli Gratin With Creamy Béchamel and Cheese (Oven-Baked)

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Prep Time 10

Cooking Time 20

Category Main Course

Cuisine French

Portions 4 Portions

Calories 400 kcal