Cauliflower gratin is the kind of side dish that can steal the spotlight from any main course. Tender cauliflower baked in a creamy cheese sauce, topped with crispy, golden breadcrumbs.
In my mind, this gratin is an elegant and guilt-free version of mac and cheese, and yes, you can quote me on that.
If you’re looking for a way to get even picky eaters to love their veggies, this dish delivers. It’s cozy, creamy, and perfect for everything from weeknight dinners to holiday spreads.
What Is a Cauliflower Gratin?
A gratin is a French-style baked dish known for its crispy, golden crust—usually made with cheese or breadcrumbs. Cauliflower gratin is a lighter twist on the classic potato gratin, where cauliflower takes center stage.
The secret to its luxurious texture lies in the Mornay sauce. It’s a cheese-enhanced béchamel sauce that’s rich, silky, and coats every floret beautifully.
Tips for Cooking and Prepping
When I make cauliflower gratin, I always start by parboiling the cauliflower for a few minutes in salted water until it’s tender but not soft. This step ensures it bakes evenly and doesn’t release too much moisture into the sauce.
For the sauce, I recommend using whole milk or half-and-half. It creates a rich base without feeling too heavy. Slowly whisk in the milk as you make the roux so it stays smooth. No lumps allowed!
And don’t skip seasoning the breadcrumb topping. I like mixing mine with melted butter, a little garlic powder, and dried herbs like thyme or parsley. It makes all the difference once it’s baked and crispy.
What Cheese Should You Use?
Cauliflower gratin is all about balance. You want cheeses that melt smoothly but also add depth. A classic combo is Gruyère and Parmesan. Gruyère gives that creamy melt, while Parmesan adds a sharp, nutty flavor.
If you can’t find Gruyère, Swiss, cheddar, or fontina are great substitutes. Mixing two or three kinds of cheese creates a richer flavor profile.
For a milder, more kid-friendly version, try half cheddar and half mozzarella. If you’re going fancy, add a spoonful of cream cheese or mascarpone for extra creaminess.
What Is Mornay Sauce (and How to Make It Perfectly)?
A mornay sauce is simply a béchamel sauce (milk + butter + flour) with cheese added. It’s the foundation of most creamy gratins.
Here’s how to make it right:
Melt butter in a saucepan, whisk in flour, and cook for a minute until it smells nutty — that’s your roux. Gradually add warm milk, whisking constantly until smooth and thickened.
Remove from heat, then stir in your cheese until melted. Season with salt, pepper, and a pinch of nutmeg for warmth.
The key here is not to rush things. Let the sauce thicken gently and stir until silky. This is what gives the gratin its luxurious texture.
Can I Use Frozen Cauliflower?
Yes, you can! Frozen cauliflower works beautifully here. Just make sure to thaw and drain it well first. Too much water can make the gratin soupy.
If you have fresh cauliflower, that’s even better. Cut it into evenly sized florets for even cooking, and blanch for about 3–4 minutes before baking.
Can You Make This Vegan?
For a vegan cauliflower gratin, use plant-based butter and unsweetened oat or almond milk. Nutritional yeast adds that “cheesy” flavor, or you can melt in vegan cheese shreds instead.
Swap the breadcrumb topping with one made from crushed nuts or panko mixed with olive oil for an extra crunch. It’s rich, savory, and still incredibly satisfying.
What to Serve It With
Cauliflower gratin pairs perfectly with roast chicken, grilled steak, baked salmon, or even holiday ham. It’s also great alongside other vegetable sides like green beans or glazed carrots.
For a vegetarian meal, serve it with a mixed green salad and crusty bread.
Storage and Make-Ahead Tips
You can prepare the gratin up to a day in advance. Assemble everything, cover tightly, and refrigerate until ready to bake. When you’re ready, bake as usual; just add 5–10 extra minutes since it’ll be cold.
Leftovers store well in the fridge for up to 4 days. Reheat in the oven at 350°F (175°C) until warmed through.
You can also freeze cauliflower gratin before baking. Wrap tightly, freeze for up to 1 month, then thaw overnight before baking. If already baked, let it cool completely before freezing and reheat gently covered with foil.
Creamy Cauliflower Gratin Recipe
Image credit: @pizzeriamozza
Ingredients
For the Gratin Base
- 1 large head of cauliflower, cut into florets (about 6 cups)
- 2 tablespoons butter
- 2 tablespoons all-purpose flour
- 2 cups milk (or half-and-half)
- ½ teaspoon salt
- ¼ teaspoon black pepper
- Pinch of nutmeg
For the Cheese Sauce (Mornay Sauce)
- 1 cup shredded Gruyère cheese
- ½ cup grated Parmesan cheese
For the Topping
- ½ cup breadcrumbs (homemade or store-bought)
- 1 tablespoon melted butter
- ½ teaspoon dried thyme or parsley
Instructions
- Preheat the oven. Set to 375°F (190°C) and lightly grease a baking dish.
- Parboil the cauliflower. Cook florets in salted water for 3–4 minutes until just tender. Drain and set aside.
- Make the roux. Melt butter in a saucepan over medium heat. Stir in flour and cook for 1 minute.
- Add milk and thicken. Gradually whisk in milk until smooth and thickened. Season with salt, pepper, and nutmeg.
- Add cheese. Remove from heat and stir in Gruyère and Parmesan until melted and creamy.
- Assemble. Spread the cauliflower in the baking dish, pour the cheese sauce over it, and mix gently.
- Top with breadcrumbs. Combine breadcrumbs, butter, and herbs, then sprinkle over the top.
- Bake. Bake for 25–30 minutes until bubbly and golden brown. Let rest 5 minutes before serving.
Featured image credit: @storeboughtisfine
