This post may contain affiliate links. Please read our disclosure policy.

This cauliflower au gratin is creamy, cheesy, and baked to golden perfection—basically everything you want in a comfort food side dish. Tender cauliflower is coated in a rich homemade cheese sauce and topped with a crispy, buttery breadcrumb layer. It’s the kind of recipe that turns even cauliflower skeptics into instant fans.

If you love cheesy sides, be sure to try my Easy Cheesy Potatoes and Amish Funeral Potatoes too!

Serving of cauliflower au gratin served on a white round plate.

Why you’ll love this cauliflower au gratin recipe!

I first made this cauliflower au gratin when I needed a new side dish to serve with Thanksgiving dinner, alongside our usual mashed potatoes and sweet potato casserole. I always like pairing those old stand-by recipes with new favorites, but ever since that first Thanksgiving cauliflower au gratin, my family has been asking for this side dish nonstop. I guess it’s going to be on regular rotation now!

Believe me when I say that this recipe will make everyone a cauliflower lover. I think it’s the homemade cheese sauce that no one can resist. The tender cauliflower is coated in a gruyere (also an ingredient in my scalloped potatoes recipe and potatoes au gratin!) and white cheddar sauce, then baked to get a crispy, golden-brown top. SO good!

  • Incredibly Creamy and Cheesy: The combination of white cheddar and gruyere creates a rich, velvety sauce that coats every bite of cauliflower.
  • Perfect Holiday Side Dish: This dish fits right in next to classics like mashed potatoes and stuffing, making it ideal for Thanksgiving, Christmas, or any big gathering.
  • Turns Cauliflower Into Comfort Food: Even if you’re not usually a fan of vegetables, this recipe transforms cauliflower into something indulgent and irresistible.
  • Easy to Make Ahead: You can prep it in advance and bake when needed, which is a huge win for busy holidays or weeknight dinners.

Ingredient Notes

All of the ingredients for cauliflower au gratin in bowls on a countertop.

See recipe card below this post for ingredient quantities and full instructions.

  • Cauliflower florets – Fresh is best, but frozen (thawed) works too.
  • Salt – For seasoning the boiling water.
  • Butter – Adds richness and helps create the roux.
  • Flour – Thickens the cheese sauce.
  • Whole milk – Creates a creamy, smooth base for the sauce.
  • Black pepper – Adds a subtle kick.
  • White cheddar cheese – Sharp and flavorful.
  • Gruyere cheese – Melts beautifully and adds a nutty depth.
  • Breadcrumbs – For that crispy, golden topping.

Variations

Here are a few ways you can switch up this recipe and make it your own.

  • Use a tablespoon of cornstarch in place of flour and omit the breadcrumbs to make a gluten-free cauliflower au gratin.
  • Scoop the cauliflower cheese mixture into small 6-ounce ramekins before baking to create individual cauliflower gratins.
  • Swap the cheddar cheese or gruyere for your favorite melting cheese. Monterey jack, gouda or colby cheese will all be delicious.
  • Use broccoli in place of cauliflower to make a tasty broccoli au gratin recipe.

How to Make Cauliflower Au Gratin

Cheese sauce spread in casserole dish.
  1. Make the cheese sauce: Melt butter in a saucepan over medium heat. Whisk in the flour and cook for about 1 minute to form a roux. Slowly add the milk, whisking constantly until thickened and smooth. Remove from heat and stir in the cheddar, gruyere, and pepper. Mix until the cheese is fully melted and the sauce is creamy and spread half into a baking dish.
Cauliflower spread over cheese sauce.
  1. Add the cauliflower: Distribute it in an even layer over the cheese sauce.
Cauliflower au gratin before adding topping.
  1. Add the remaining cheese: Pour it evenly over the cauliflower.
Cauliflower au gratin before baking.
  1. Add the topping and bake: Mix breadcrumbs with the remaining cheese and sprinkle over the dish. Drizzle melted butter on top. Bake at 375°F for about 25 minutes, or until the top is golden brown and the sauce is bubbling.
Spoon full of cauliflower au gratin.

Serving Suggestions

I mentioned at the beginning that I love to serve this cauliflower au gratin with Thanksgiving dinner. It is really tasty with any kind of meat, from garlicky steak bites to a simple baked chicken breast.

How to Store Cauliflower au Gratin

Once the au gratin is baked, it needs to be stored in the fridge. All leftovers should be wrapped tightly and kept refrigerated for up to 4 days. Microwave a portion of gratin for about 1 minute when you are ready to enjoy it again. 

To freeze, wrap the entire casserole dish with plastic wrap and freeze for up to three months. Thaw the casserole overnight in the fridge, then pop it in a 350ºF oven for 10 minutes to reheat. 

Frequently Asked Questions

What is cauliflower au gratin?

It’s a baked dish made with cauliflower and a creamy cheese sauce, topped with breadcrumbs or extra cheese and baked until golden.

Can I make it ahead of time?

Yes! Assemble the dish, cover, and refrigerate. Bake when ready to serve.

Why is my sauce grainy?

This usually happens if the cheese is added over too much heat. Remove the sauce from heat before stirring in the cheese.

Can I use frozen cauliflower?

Absolutely. Just thaw it first and reduce the cooking time slightly since it’s already soft.

More Cauliflower Recipes You’ll Love

💌 Love easy recipes? Join my newsletter and get my Top 10 Reader-Favorite Recipes eBook FREE! Sign up here.

Need help with this recipe?
Click the buttons below to summarize it, adjust for diets, swap ingredients, or ask your own questions!

Cauliflower au Gratin

This cauliflower au gratin recipe is creamy, cheesy, and baked to golden perfection—an easy side dish for holidays or weeknights!
5 from 1 vote
Course: Side Dish
Cuisine: American
Servings: 4 servings
Prep Time: 15 minutes
Cook Time: 30 minutes
Total Time: 45 minutes

Ingredients  

  • 2 pounds cauliflower florets
  • 1 tablespoon salt
  • ¼ cup butter
  • 3 tablespoons flour
  • 2 cups whole milk
  • ½ teaspoons ground black pepper
  • 1 cup shredded white cheddar cheese
  • ½ cup grated gruyere cheese
  • ¼ cup bread crumbs

Instructions 

  • Preheat your oven to 375ºF.
  • Bring a large pot of water to a boil and add the tablespoon of salt.
  • Add the cauliflower to the pot and boil for 5 minutes. The florets will be slightly soft. Drain in a colander and set aside.
  • Melt two tablespoons of the butter in a medium sized pot over medium heat.
  • Add the flour to the pot and whisk, stirring constantly for one minute. The flour and butter mix may start to turn brown but this is okay—it’s flavor!
  • Pour the milk into the pot and whisk until the milk begins to boil. Boil for one minute, whisking constantly.
  • Remove the pot from the stovetop and add the pepper, ½ cup cheddar cheese and gruyere. Whisk until the cheese melts.
  • Pour half of the cheese sauce in the bottom of a 8×11 baking dish and spread it across the whole dish.
  • Add the cooked cauliflower florets to the pan, making an even layer across the bottom.
  • Pour the rest of the cheese sauce over the cauliflower florets.
  • In a small bowl, toss together the breadcrumbs and remaining ½ cup of cheddar cheese. Sprinkle this mix over the cauliflower in the pan.
  • Melt the remaining 2 tablespoons of butter and drizzle it over the top of the breadcrumbs.
  • Bake the cauliflower gratin for 25 minutes in the oven. The top should be completely golden brown and the cheese sauce will be bubbling in the pan.
  • Serve while hot!

Video

Notes

  • Don’t overcook the cauliflower: You want it just tender before baking so it doesn’t become mushy.
  • Use freshly shredded cheese: It melts better and creates a smoother sauce than pre-shredded varieties.
  • Whole milk makes a difference: It gives the sauce that rich, creamy texture that makes this dish so special.
  • Let it rest before serving: A few minutes of rest time helps the sauce thicken slightly and makes serving easier.

Nutrition

Calories: 375kcal | Carbohydrates: 29g | Protein: 22g | Fat: 20g | Saturated Fat: 11g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 5g | Cholesterol: 61mg | Sodium: 2211mg | Potassium: 979mg | Fiber: 6g | Sugar: 11g | Vitamin A: 638IU | Vitamin C: 109mg | Calcium: 584mg | Iron: 2mg
Did you make this recipe?Mention @kasey_allthingsmamma or tag #allthingsmamma!

Categories: , , , ,

About Kasey Schwartz

For over 15 years, Kasey Schwartz, the mastermind behind All Things Mamma, has been the ultimate go-to for mouthwatering family recipes. Her work has been featured on Today.com, Buzz Feed, Better Homes and Gardens, and more, making her your go-to mom next door for all things delicious and family-friendly.

5 from 1 vote (1 rating without comment)

Leave a Reply

Your email address will not be published. Required fields are marked *

Recipe Rating




This site uses Akismet to reduce spam. Learn how your comment data is processed.