Cauliflower Casserole (The Best Thing to Happen to Cauliflower)
Oct 14, 2025
This Cauliflower Casserole recipe is creamy and cheesy with a buttery, crispy breadcrumb topping. Done in 30 minutes and totally craveworthy!
This Cauliflower Casserole recipe is one of the coziest vegetable-based winter casserole recipes.
It’s perfect for holiday meals, or a comforting side dish anytime. I even serve it as a main dish, like a veggie-powered alternative to baked macaroni and cheese (and I’ve never seen kids inhale cauliflower so fast!).
Cauliflower Casserole Ingredients
Here is everything you’ll need to make this recipe:
- Cauliflower: About 8 cups florets, roughly a large head cauliflower (or 2 pounds). Fresh works best for a tender yet firm texture after baking, but frozen florets or cauliflower rice work, too.
- Butter
- Onion
- Garlic
- All-purpose flour
- Whole milk
- Sour cream
- Cheese: I like sharp cheddar cheese for bold flavor, but you can use another type of cheese that melts well, like monterey jack cheese or mozzarella cheese.
- Parmesan cheese
- Dijon mustard
- Kosher salt and black pepper
- Cayenne pepper: or smoked paprika for flavor with no heat
- Panko breadcrumbs
- Olive oil: Helps the crumbs brown and crisp.
- Garnishes: Minced fresh parsley, green onion or fresh chives are great. Add some bacon to make it a loaded cauliflower casserole recipe!
Ingredient quantities in the recipe card at the bottom of the article.
Substitutions and Variations
- Vegetables: Swap half or all of the cauliflower for broccoli, or add sautéed mushrooms, spinach, or chopped red bell pepper.
- Cheese variations: Use some Gruyère or Fontina. Swap sour cream with soft cream cheese if that’s what you’ve got.
- Make it gluten free: Use a 1 to 1 gluten-free flour blend. Swap panko for GF crumbs or crushed GF crackers.
Tools to Grab
- Large pot, colander, and large bowl
- Medium saucepan and whisk
- Wooden spoon or spatula
- 8×11 or 9×9 inch baking dish
- Knife and cutting board
If you love cauliflower as much as I do, try my Potato and Cauliflower Curry recipe (Aloo Gobi), Baked Cauliflower Wings and Curried Cauliflower and Quinoa Soup.
How to Make Cauliflower Casserole: An Easy Guide
These are my easy steps to savory, creamy, deliciousness that’s a satisfying low carb alternative to au gratin potatoes.
Prepare the Oven and Baking Dish
Preheat your oven to 400ºF, 200ºC. Lightly grease an 8×11 or 9×9 inch baking dish to prevent sticking.
Cook the Cauliflower
Cut the cauliflower head down to bite-sized pieces.
Bring a large pot of salted water to a boil. Add the florets and cook 3 to 4 minutes until just tender. Drain thoroughly and let steam dry in a colander.
Make the Sauce Base
In a saucepan over medium heat, melt butter. Add onion and cook until softened, about 5 minutes. Stir in garlic and cook 1 minute until fragrant.
Thicken the Sauce
Sprinkle flour over onion and garlic, whisking constantly, and cook 1 minute. Slowly whisk in milk and cook until thickened, about 3 to 5 minutes.
Combine Sauce Ingredients
Remove from heat. Stir in sour cream, 1 cup cheddar, Parmesan, Dijon, salt, pepper, and cayenne if using.
Mix Cauliflower and Sauce
If the saucepan is large enough, gently fold cauliflower into the sauce, then transfer mixture to the baking dish. Otherwise, add cauliflower to the dish, pour sauce over, and fold together there. Taste and adjust salt if needed.
Prepare the Topping
Combine panko with olive oil and the remaining 1 cup cheddar. Sprinkle evenly over the casserole.
Bake and Serve
Bake 15 to 20 minutes until bubbling and golden. Rest 5 minutes. Garnish with bacon and green onion if you like. Serve warm.
3 Common Mistakes When Making Cauliflower Casserole
- Overcooking the cauliflower: Parboil just 3 to 4 minutes until fork tender, then drain and steam dry to avoid a watery bake.
- Skipping the sauce thickening: Whisk and simmer until the sauce coats a spoon, about 3 to 5 minutes, or it can separate.
- Under seasoning: Taste the sauce before combining with cauliflower and adjust salt, pepper, and mustard.
Make Ahead and Storage
This casserole can be assembled up to 1 day ahead and baked when ready.
Storing
- Store leftovers in an airtight container in the refrigerator up to 4 days. Reheat portions as needed.
Freezing
- Freeze the unbaked casserole without the topping for up to 2 months. Thaw in the fridge overnight, add topping, then bake.
Reheating
- Reheat individual portions in the microwave or warm the full casserole at 350ºF until heated through. Cover with foil to protect the top.
Other Favorite Side Dish Recipes
- Green Bean Casserole (with Homemade Crispy Onions!)
- Candied Brussel Sprouts
- Soft and Tender Cornbread Casserole
- Quick and Easy Glazed Carrots
Final Notes, Pro Tips + Science-Based Secrets
- Steam dry the florets: After draining, let them release steam in the colander so the casserole stays creamy, not watery.
- Grate your own cheese: Freshly grated melts smoother than pre-shredded with anti-caking agents.
- Golden topping trick: Broil 1 to 2 minutes at the end for extra crunch, watch closely.
- Salt the water well: If the boil water was well salted, the seasoning should be balanced. If not, add a pinch to the sauce.
FAQs About Cauliflower Casserole
Just skimming this article? Here are common questions answered.
Fresh thyme, chives, and parsley pair well with cauliflower. Fold chopped herbs into the sauce after thickening, or sprinkle over the baked casserole as a fresh garnish right before serving.
Yes, frozen works. Thaw completely and drain well. Pat dry if needed so excess water does not thin the sauce and soften the topping during baking.
Do not overcook the florets. Parboil just until tender, then steam dry in a colander. Thicken the sauce until it coats a spoon before combining.
Absolutely. Assemble up to 1 day in advance without the breadcrumb topping, refrigerate covered, then add the topping and bake as directed when ready.
Best Cauliflower Casserole
Ingredients
- 8 cups cauliflower florets (2 lbs, about large head)
- 2 tbsp butter
- 1 cup finely chopped onion
- 2 tsp minced garlic
- 2 tbsp all purpose flour
- 1 ½ cups whole milk
- ½ cup sour cream
- 2 cups grated sharp cheddar divided
- ½ cup freshly grated Parmesan
- 1 tsp Dijon mustard
- ½ tsp kosher salt or to taste
- ¼ tsp freshly ground black pepper
- ¼ tsp cayenne optional
- ½ cup panko breadcrumbs
- 1 tbsp olive oil
- 2 slices cooked bacon crumbled, optional
- 1 finely sliced green onion optional
Instructions
- Preheat oven to 400ºF. Lightly grease an 8×11 or 9×9 inch baking dish.
- Bring a large pot of generously salted water to a boil. Add cauliflower and cook 3 to 4 minutes until just tender. Drain well and let steam dry in the colander.
- Melt butter in a saucepan over medium heat. Add onion and cook until soft, about 5 minutes. Stir in garlic and cook 1 minute.
- Sprinkle in flour and cook, whisking, 1 minute. Gradually whisk in milk. Cook until thickened, about 3 to 5 minutes.
- Remove from heat. Stir in sour cream, 1 cup cheddar, Parmesan, Dijon, salt, pepper, and cayenne if using.
- Fold in cauliflower and pour into the baking dish, or add cauliflower to the dish and fold sauce in there. Taste and add a pinch of salt if needed.
- Stir panko with olive oil and remaining 1 cup cheddar. Sprinkle over top.
- Bake 15 to 20 minutes, until bubbling and golden. Rest 5 minutes. Top with bacon and green onion if using.
Notes
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Swapped the sour cream with Greek yogurt and it still came out creamy and delicious. Definitely saving this.
Made this for Thanksgiving and it disappeared before the turkey. Getting requests for the recipe already.