Roasted Cauliflower and Gruyère Gratin

Roasted Cauliflower and Gruyère Gratin is a cheesy side dish that is made by smothering oven-roasted cauliflower in a gruyère cheese sauce and then baking it in the oven until it is golden and bubbly.

Roasted Cauliflower and Gruyère Gratin in two white vintage round casserole dishes on a wooden background.

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Every night when we have dinner, I make a veggie side to go with whatever protein we're having.  I usually like to roast veggies, but I'm also big on casserole-type sides, too.  The other night I decided to combine the two and make this uber cheesy roasted cauliflower gratin.

What makes this dish so yummy is that the cauliflower is roasted in the oven before it's baked with the cheese sauce.  Roasting veggies gives them that gorgeous golden caramelization that makes my mouth water.  I seriously think I could just eat roasted veggies forever.  I simply adore them!

I love cheese just as much as I love roasted veggies, so I topped the roasted cauliflower with a gruyère cheese sauce, made with onions, garlic, and nutty shredded gruyère.  Fabulous, I tell ya.

I poured that rich cheese sauce right on top of the roasted cauliflower.  Oh, the decadence!  Sinful, right?  Oh so sinful, and oh so good.

Roasted Cauliflower and Gruyère Gratin in two white vintage round casserole dishes on a wooden background.

To make a gratin, however, you've got to have a cheesy crunch on top, so next came more cheese (oh, yeah) and some panko breadcrumbs.  The panko breadcrumbs add the perfect texture to the top of the casserole.  And the cheese?  Well, you can never have too much cheese.  That's my opinion and I'm sticking to it.  The more cheese, the merrier!

After a quick bake in the oven, the outcome is a decadent, creamy, cheesy, earthy, veggie side dish that is out of this world. It really is the best cauliflower gratin recipe! We had it as a side dish accompanying our steak, but it would be just as good with roasted chicken or pork chops!

I'm thinking it might even steal the show on Thanksgiving or Christmas.

If you've been looking for a way to make your cauliflower the star at your dinner table, then skip the steaming and roast it.  Then smother it in a cheese sauce and bake it.  Un-be-LIEV-ably good!

Roasted cauliflower in a white round vintage casserole dish on a wooden background.

How To Make Easy Cauliflower Gratin

Cauliflower gratin is easy to make at home! First, roast a head of cauliflower. Next, top it with a luscious cheese sauce. Finish with freshly grated shredded cheese and breadcrumbs before baking in the oven until golden and bubbly. See below for a detailed ingredients list and instructions.

What Does Gratin Mean?

A gratin is defined as a dish with a light browned crust of breadcrumbs or melted cheese. The panko breadcrumb and gruyere cheese that top the cauliflower florets make this recipe a gratin.

Cheese sauce and a whisk in a saucepan.

Do I Have to Roast the Cauliflower?

You don't have to roast the cauliflower if you prefer to prepare it another way, but the roasted caramelization adds so much to the full flavor of the casserole. I highly suggest taking the time to roast it!

Cauliflower Gratin Variation Suggestions

Try one of the following twists to make your cauliflower your own:
  • Add broccoli to the mix for a two veggie casserole.
  • Top with crumbled bacon for an extra rich presentation.
  • Add additional herbs like fresh rosemary or oregano.
  • Add some cajun seasoning to your cauliflower before roasting for some added spice.

Roasted cauliflower topped with melted white cheese sauce in a vintage white casserole dish on a wooden background.

What Does Gruyère Cheese Taste Like?

Gruyère cheese has a firm texture with a nutty, smooth, rich flavor. It can be compared to the taste of swiss, but it has a more complex, robust flavor.

What to Serve With Easy Baked Cauliflower Gratin

Cauliflower cheese gratin is a gorgeous side dish that pairs well with most proteins. Try it with these favorites:

Roasted cauliflower topped with melted white cheese sauce  and shredded cheese in a vintage white casserole dish on a wooden background.

How To Store Cauliflower Gratin

Leftover cauliflower gratin casserole can be store in the refrigerator in an air tight container for up to four days. Freeze for up to three months.

More Yummy Cauliflower Recipes

Looking for more awesome cauliflower recipes? Check out these popular recipes from the archives:

If you try this recipe, I'd love to know what you think in the comments below. Enjoy!

Roasted Cauliflower and Gruyère Gratin in a white vintage round casserole dish on a wooden background.

Roasted Cauliflower and Gruyère Gratin

Yield: 6 servings
Prep Time: 15 MINUTES
cook time: 25 MINUTES
total time: 40 MINUTES
Roasted Cauliflower and Gruyère Gratin is made by smothering roasted cauliflower in a gruyère cheese sauce and baking it until golden and bubbly.


1 large head cauliflower, cored and cut into florets
1/4 cup olive oil
1/2 teaspoon salt
1/2 teaspoon dried thyme
1/4 teaspoon fresh ground black pepper
1/4 cup butter
1/3 cup onion, finely chopped
1 clove garlic, minced
3 tablespoons flour
2 cups hot milk
1/8 teaspoon ground nutmeg
2 cups gruyère cheese, shredded
1/4 cup panko breadcrumbs


  1. Preheat oven to 425 degrees. In a large bowl, toss the cauliflower, olive oil, salt, thyme, and pepper. Place onto a foil-lined baking sheet in a single layer. Roast for 10 minutes, stir, then roast for an additional 10 minutes. Remove from the oven and reduce the heat to 375 degrees.
  2. Meanwhile, melt the butter over medium heat in a saucepan.  Add the onions and cook for 3 minutes.  Add the minced garlic and cook for 1 minute more.  Add the flour to the pan and stir constantly with a whisk for 1-2 minutes, or until the flour begins to turn golden.  Pour the milk into the saucepan, continuing to whisk until the mixture comes to a boil.   Boil for 1 minute, or until thickened.  Remove from the heat and stir in the nutmeg and gruyère cheese, reserving a 1/2 cup for topping.
  3. Spoon a little bit of the sauce into the bottom of a 2-quart glass baking dish.  (I used two small ones.)  Pour the cauliflower into the dish and top with the remaining sauce.  Mix together the remaining 1/2 cup of cheese and the breadcrumbs.  Spread evenly over the top and drizzle lightly with olive oil.
  4. Bake in the 375 degree oven for 25 minutes, or until golden brown and bubbly.  Let cool 5 minutes before serving.


Source: Adapted from a recipe by Ina Garten

Nutrition data should not be considered a guarantee. Please see our full Nutrition Data Disclosure.


  1. Can these be prepped before hand, kept in the refrigerator and then baked a day or two later?

  2. I know this will sound goofy...i know the term sinful tasting food is suppose to sound like it is a good thing, but we never understood that goofy term...sinful tasting sounds bad to many of my friends, and so if it is sinful tasting, how can it be good? No offense, your recipes look good, it's just some of our terms seem unfitting, even tho that term is an old one...keep up the recipes, you are talented!

  3. What could I substitute for Gruyère cheese? It’s soooo expensive at 2 cups.

    1. I always use swiss cheese.

    2. I think a decent quality sharp cheddar would work in a "plan B" situation!

  4. Also cholesterol everyone posting butter cream cheese doesn’t create a healthy low fat dish.

  5. Why are there no stars to give this?! Def a 5 star dish! We had this tonight with filet mignon for our Christmas Eve dinner. I used a small head of cauliflower and cut all ingredients in half. It’s so decadent we will still get 4 servings out of it. Thank you so much for sharing. Will def make again!