Cauliflower au Gratin
Updated Aug 22, 2025
This post may contain affiliate links. Please read our disclosure policy.
This is a downright irresistible casserole with a rich cheesy sauce, crunchy breadcrumb topping, and tender cauliflower.
This dish is a cozy, irresistible casserole — and a testament to how a vegetable can steal the dinner show. Fresh cauliflower florets are tucked into a rich, creamy cheese sauce (think Gruyére and Parmesan), topped with buttery crisp breadcrumbs, and baked until bubbling and golden. Pancetta or bacon adds a savory punch, but the dish can be just as wonderful without. Cauliflower au Gratin is perfect for a holiday buffet or as a luxurious side for roasted chicken, but serve it with salad and it holds its own as a main course too.
The flour, along with the cheeses and milk, creates a rich, creamy sauce that isn’t at all watery.There are easy tips for making it ahead of time and/or gluten-free. Cauliflower gratin is classic, flexible, and always crowd-pleasing.
This casserole is perfect for the holidays — a terrific addition to a Thanksgiving, Christmas, or New Year’s menu, and also great for Easter. If you want to serve it as a side for a weeknight dinner, it’s great with simple mains like Pan-Fried Pork Chops.
By signing up, you agree to our Privacy Policy.
What's In This Post?
Cauliflower Gratin: This is downright irresistible with a rich cheesy sauce, crunchy breadcrumb topping, and tender cauliflower.
What Does “au Gratin” Mean?
The name gratin or au gratin comes from the French word “gratiner,” which means to broil. You might also see this called a Gratiniata, Gratine, or Gratinee. Different names in different languages, but this type of dish is popular in Mediterranean cuisines, especially Italian and French, as well as American cooking.
“Au Gratin is a French term for a dish topped with a browned crust, typically using breadcrumbs, cheese, or both. It’s all about that irresistible, crispy cheesy layer on top of something wonderfully tender underneath.
Cauliflower au Gratin Questions, Asked and Answered!
Up to you! While Cauliflower au Gratin is usually a show-stopping side (perfect for holidays or Sunday dinners), it’s hearty enough to be the main event — especially with a salad on the side.
Yes! Swap out all-purpose flour for a gluten-free version in the cheese sauce, and use gluten-free breadcrumbs on top, and you’re all set.
Absolutely. Assemble it up to a day in advance, refrigerate, and bake before serving. It also reheats beautifully, making leftovers something to look forward to.
Gruyére from Switzerland gives this dish its classic flavor, but you can get creative and use sharp cheddar, fontina, or any good melting cheese you love.
GF Variation
If you want to make this a gluten-free casserole, you can use gluten-free flour instead of all-purpose flour, and gluten-free breadcrumbs as well.
How to Make Cauliflower au Gratin
- In a large, deep skillet, cook the bacon over medium-high heat, stirring frequently, until the pancetta is crispy, about 5 minutes. Transfer with a slotted spoon to a paper towel-lined plate. Leave about 1 tablespoon fat in the pan and melt 2 tablespoons of the butter in the same skillet. Toast the breadcrumbs until they are golden brown and slightly crispy, about 3 minutes. Scrape the breadcrumbs into a medium bowl.
- Return the pan to the heat and melt the remaining 2 tablespoons of butter over medium heat. Whisk in the flour and whisk frequently until the mixture is well combined and blond in color, about 2 to 3 minutes. Slowly whisk in the half-and-half or milk and bring to a simmer over medium-high heat, whisking frequently, until the mixture is bubbling and thickened. Season with salt and pepper and whisk in half of the gruyère until it’s melted, along with the cooked bacon.
- Meanwhile, bring a large pot of salted water to a boil. When the water is boiling, add the cauliflower and cook for about 4 minutes, until crisp-tender. Drain, then add the cauliflower to the sauce and toss to combine well. Transfer to a prepared baking dish.
- Add the remaining ½ cup Gruyere and the Parmesan to the bowl with toasted breadcrumbs and stir to blend. Sprinkle the mixture over the cauliflower.
- Bake for at 375 degrees for 35 to 40 minutes until bubbling around the edges and golden brown on top. Serve hot or warm.
What to Serve With Cauliflower au Gratin
More Cauliflower Recipes
Also see How to Cook Cauliflower.
Pin this now to find it later
Pin It
Cauliflower au Gratin
Ingredients
- 4 ounces thick sliced bacon or pancetta (diced)
- 4 tablespoons unsalted butter (divided)
- 1 cup fresh breadcrumbs (or panko)
- 3 tablespoons all-purpose flour
- 2 ½ cups half and half or whole milk
- Kosher salt and freshly ground black pepper (to taste)
- 1 large head cauliflower (about 3 pounds; cut into florets)
- 1 cup (4 ounces) grated Gruyere cheese (divided)
- ½ cup (about 1 ounce) grated Parmesan cheese
Instructions
- Preheat the oven to 375F. Line a plate with paper towels. Lightly oil a 1 1/2-quart baking dish or a 9-inch round or square baking pan, or spray with nonstick cooking spray.
- In a large, deep skillet, cook the bacon or pancetta over medium-high heat, stirring frequently, until crispy, about 5 minutes. Transfer with a slotted spoon to the paper towel-lined plate. Leave about 1 tablespoon fat in the pan; pour out any extra. Melt 2 tablespoons of the butter in the same skillet over medium heat. Add the breadcrumbs and cook, stirring often, until the breadcrumbs are golden brown and slightly crispy, about 3 minutes. Remove from the heat and scrape the breadcrumbs into a medium bowl. Set aside.
- Return the pan to the heat and melt the remaining 2 tablespoons of butter over medium heat. Whisk in the flour and whisk frequently until the mixture is well combined and blond in color, about 2 to 3 minutes. Slowly whisk in the half-and-half or milk and bring to a simmer over medium-high heat. Simmer, whisking frequently, until the mixture is bubbling and thickened, about 5 minutes. Season with salt and pepper and whisk in half of the gruyere until it’s melted, along with the reserved crispy pancetta.
- Meanwhile, bring a large pot of salted water to a boil. When the water is boiling, add the cauliflower and cook for about 4 minutes, until crisp-tender. Drain, then add the drained cauliflower to the sauce and toss to combine well. Transfer the sauced cauliflower to the prepared baking dish. Add the remaining 1/2 cup gruyere and the Parmesan to the bowl with toasted breadcrumbs and stir to blend. Sprinkle the mixture over the cauliflower.
- Bake for 35 to 40 minutes until bubbling around the edges and golden brown on top. Serve hot or warm.
Truly outstanding recipe. Several friends requested the recipe. I’d trust Workman’s recipe’s each time.