Easy Baked Cauliflower Gratin
This easy baked Cauliflower Gratin is a classic French side dish that's a great make-ahead recipe for serving a crowd. It's melty, cheesy and perfect for the holidays!
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What is a Gratin?
A gratin (pronounced grah-tahn) refers to any food that has been placed under a broiler to achieve a crispy, crunchy top, usually with either breadcrumbs, cheese, or both. "Gratin" or "au gratin" comes from the French word "grainer," which literally translates to "to broil."
If you love gratin as much as me, try my Classic Potato Gratin, this summery Zucchini Gratin, a Fennel and Onion Gratin, a Parsnip and Celery Root Gratin, or this Kale Gratin.
Why This Recipe Works
- An authentic French gratin recipe I learned to make in culinary school.
- Utilizes the cauliflower cooking water to make the veloute sauce rather than stock or milk, which results in a lighter, cleaner flavor that actually tastes like cauliflower.
- Can be made up to two days in advance and baked before serving.
- A little cream, a lot of cheese and a buttery, garlicky, herby breadcrumb topping make this simple cauliflower bake taste amazing.
Cauliflower - This recipe calls for using a large whole head of fresh cauliflower, but frozen cauliflower can be used as well. Substitute about 2 ½ lbs or 6 heaping cups of frozen cauliflower florets. Having a little more or less won't affect the recipe.
Gruyere Cheese - Look for a good quality aged Gruyere, which is the traditional French cheese used for a gratin. If Gruyere is hard to find or out of your price range, use Emmental, Jarlsberg or good quality Swiss cheese.
Nutmeg - Freshly grated whole nutmeg is best, otherwise make sure your ground nutmeg is fresh and hasn't been sitting in your pantry for years. The flavor degrades over time so it won't have the same impact. If you can't remember when you bought it, it's time to get a new one.
Breadcrumbs - This cauliflower bake calls for Panko breadcrumbs because I always have them on hand and they're always light and crunchy, but homemade breadcrumbs made from stale bread would also be great.
*Find the full ingredient list in the recipe card below!
Step by step instructions
- Add the cauliflower to a medium pot, then add just enough room temperature water to barely cover. The goal is to use less water in order to achieve a more concentrated cauliflower flavor, so it's okay if some pieces are sticking out of the top.
- Bring the water up to a simmer, then cover and cook until the cauliflower pieces are al dente, about 2-3 minutes. Drain the cauliflower well and reserve the cooking water.
- Preheat the oven to 400 degrees F and butter the inside of a medium casserole dish.
- Melt butter in a medium sauce pan over medium heat, then whisk in the flour until it absorbs all the butter, about 1-2 minutes.
- Slowly whisk in 1 ½ cups of the reserved cauliflower cooking water (it should still be warm), then continue whisking until it comes up to a boil.
- Lower the heat, continue whisking, and cook for 2-3 minutes until thickened.
- Whisk in the heavy cream, salt and pepper, then turn off the heat.
- Stir in the nutmeg and ⅓ of the Gruyere cheese (about 1 cup) until the cheese is melted.
- Add the well-drained cauliflower to the cheese sauce and mix to combine. Taste for seasoning and adjust as needed - it will likely need a bit more salt and pepper.
- Scrape the cauliflower mixture into the buttered casserole dish, being sure to get every last bit of cheese sauce in there.
- Sprinkle with the remaining Gruyere cheese, then set aside while you make the topping.
- Melt the butter in a medium sauté pan over medium heat, then add the garlic and stir around until it starts to sizzle.
- Add the panko breadcrumbs, thyme leaves and a pinch of salt and pepper, then continue to stir around until light golden brown, about 5 minutes.
- Spread the breadcrumbs on top of the cauliflower in an even layer.
- Bake for about 20 minutes, or until the breadcrumbs have darkened a few shades and it's bubbling up around the sides.
- Allow the gratin to cool down for about 10 minutes before serving.
Tips for Success
- Be careful not to overcook the cauliflower while boiling, it should still be slightly firm or al dente. The time will depend on the size of your florets - check them every minute or so with a fork.
- It's really important that the cauliflower is drained very well and does not have a lot of extra liquid before adding to the cheese sauce or it will be watery.
- Use a deep dish pie plate or cast iron skillet in place of a casserole dish if desired.
FAQ
Yes! This cauliflower gratin would taste equally as good with broccoli, Romanesco cauliflower or even Brussels sprouts!
Yes! Make the recipe as directed but skip the baking and refrigerate, covered, for up to 48 hours in advance. Bake in a 350 degree F oven, covered, for about 15-20 minutes, then remove the cover and bake for another 10-15 minutes until golden brown on top and bubbling around the sides.
I love this as a side dish in the fall and winter along side a roast chicken, pork chops, or roasted beef. It's also lovely on it's own as a lighter meal with a salad to cut through the richness. It's also a very popular side dish to serve at Thanksgiving, Friendsgiving and other holiday dinners!
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Easy Baked Cauliflower Gratin
Ingredients
For the Filling:
- 1 large head of cauliflower trimmed and cut into florets (about 2 ½ lbs or 6-7 heaping cups)*
- 3 tablespoons butter plus more for greasing the dish
- ¼ cup all purpose flour
- 1 ½ cups reserved cooking water
- ¼ cup heavy cream
- 2 teaspoons Kosher salt plus more to taste
- freshly ground pepper to taste
- ¼ teaspoon fresh nutmeg
- 6 ounces Gruyere cheese grated (about 3 cups), divided
For the Topping:
- 3 tablespoons butter
- 1 clove garlic finely minced
- 1 ¼ cups panko breadcrumbs
- 1 teaspoon fresh thyme leaves
- salt and pepper to taste
Instructions
- Add the cauliflower to a medium pot, then add just enough room temperature water to barely cover. The goal is to use less water in order to achieve a more concentrated cauliflower flavor, so it's okay if some pieces are sticking out of the top.
- Bring the water up to a simmer, then cover and cook until the cauliflower pieces are al dente, about 2-3 minutes. Drain the cauliflower well and reserve the cooking water.
- Preheat the oven to 400 degrees F and butter the inside of a medium casserole dish.
- Melt butter in a medium sauce pan over medium heat, then whisk in the flour until it absorbs all the butter, about 1-2 minutes.
- Slowly whisk in 1 ½ cups of the reserved cauliflower cooking water (it should still be warm), then continue whisking until it comes up to a boil.
- Lower the heat, continue whisking, and cook for 2-3 minutes until thickened.
- Whisk in the heavy cream, salt and pepper, then turn off the heat.
- Stir in the nutmeg and ⅓ of the Gruyere cheese (about 1 cup) until the cheese is melted.
- Add the well-drained cauliflower to the cheese sauce and mix to combine. Taste for seasoning and adjust as needed - it will likely need a bit more salt and pepper.
- Scrape the cauliflower mixture into the buttered casserole dish, being sure to get every last bit of cheese sauce in there.
- Sprinkle with the remaining Gruyere cheese, then set aside while you make the topping.
- Melt the butter in a medium sauté pan over medium heat, then add the garlic and stir around until it starts to sizzle.
- Add the panko breadcrumbs, thyme leaves and a pinch of salt and pepper, then continue to stir around until light golden brown, about 5 minutes.
- Spread the breadcrumbs on top of the cauliflower in an even layer.
- Bake for about 20 minutes, or until the breadcrumbs have darkened a few shades and it's bubbling up around the sides.
- Allow the gratin to cool down for about 10 minutes before serving.
Notes
- *Use about 2 ½ lbs or 7 cups of frozen cauliflower.
- Be careful not to overcook the cauliflower while boiling, it should still be slightly firm or al dente. The time will depend on the size of your florets - check them every minute or so with a fork.
- It's really important that the cauliflower is drained very well and does not have a lot of extra liquid before adding to the cheese sauce or it will be watery.
- Use a deep dish pie plate or cast iron skillet in place of a casserole dish if desired.
- This cauliflower gratin can be made entirely in advance. Reheat in a 350 degree F oven covered for about 15 minutes, then remove the cover and bake for another 10-15 minutes until bubbling around the sides.
I followed the recipe to the T, and it was OUTSTANDING!
So glad you loved the recipe! Thank you so much for leaving a review!:)
How do I make it ahead of time? Do I assemble it, refrigerate and bake the day of?
Yes! Make the recipe as directed but skip the baking and refrigerate, covered, for up to 48 hours in advance. Bake in a 350 degree oven, covered, for about 15-20 minutes, then remove the cover and bake for another 10-15 minutes until golden brown on top and bubbling around the sides. Hope this helps!
Compliments galore!
This is a winner.
So happy you enjoyed it! Thanks for leaving a review!
I made it with broccoli and cauliflower, used half and half instead of heavy cream. But it was still quite rich. I made my own breadcrumbs from stale sourdough bread. The fresh grated nutmeg was definitely a good move. Delicious! Thank you. foe sharing.
Sounds great! So glad you enjoyed it. Thanks for leaving a review!
I am making the 3X recipe of Easy Baked Cauliflower Au Gratin, which calls for 4.5 cups reserved cooking water in the ingredients list. But in the directions, it says to whisk in 1.5 cups of the reserved cooking water. The other 3 cups of cooking water are not mentioned again. So may I assume the 1.5 cups is supposed to be 4.5 cups or is another part missing? Can I cook this at 350 degrees with other foods that will be reheating? It sounds delicious. Thanks.
4.5 cups is correct. Unfortunately the recipe card does not change any quantities in the instructions, only in the ingredient list. I'm sorry for the confusion, hope this helps.
Amazing recipe! I make this all the time now. I can easily make it a meal
I love that!!
Absolutley love this recipe
Thank you!
SO good. Love how straight forward the recipe is. Doubling next time. Would you bake it in a 9x13 dish?
SO glad you love the recipe! Yes, 9x13 would be perfect for doubling.
Was a hit at the family Christmas dinner - so easy and yummy! Even better the next day reheated. Will definitely make again!
So glad everyone enjoyed it!
I made this recipe for Easter the first time it was published. Now it's a family favorite not only for Easter, it's on the weeknight dinner recipe rotation! Delicious.
Chrissy
so glad you enjoyed it, Chrissy!!
Glad I found your website through pinterest. These recipes are awesome - do you know if it is vegan friendly? I want to make it for the holidays and some folks in my family are vegan
Thank you! You can try substituting a vegan cheese such as Daiya and using almond milk, vegan butter to make it vegan. I haven't tried it myself, so if you do I'd love to know how it turns out!
This was delicious!
thank you!!
My new go to for baked cauliflower. Didn't change a thing. Delicious.
Awesome!!!
Glad you brought the cauliflower back. I can totally relate to everything tasting the same, and I love the idea of using the cooking water rather than stock. My gratins are much lazier than this, but that veloute makes it look like mac and cheese in the best way.
I'll take a lazy gratin over no gratin any day!