Cauliflower Au Gratin

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If you’re on the hunt for a cheesy, comforting side dish that even the most stubborn cauliflower haters will love, this Cauliflower Au Gratin is about to become your new best friend. With tender cauliflower florets smothered in a rich, creamy cheese sauce and topped with golden brown cheddar, this dish is the perfect blend of comfort and flavor. Whether you’re planning a holiday dinner or just looking to upgrade your weeknight meal, this cauliflower gratin recipe will steal the show. Similar to Scalloped Potatoes but made with cauliflower, this low-carb, cheesy side dish is what dreams are made of.

Why You’ll Love This Recipe!

When I need a fast veggie-packed side dish during the week or want something creamy and cheesy for the holidays, I love making this Cauliflower Gratin. While the creamy cheese sauce is silky smooth, the cauliflower keeps it light and easy on the carbs so you can feel a little better about this recipe versus Funeral Potatoes or Mashed Potatoes.

While I big puffy heart eyes LOVE potatoes, cauliflower is the healthier cousin that tastes nearly as good. Topping steamed cauliflower with a creamy sauce, finishing it off with grated cheddar cheese and baking it into a creamy and cheesy casserole becomes a great addition to nearly any meal.

Ingredients Needed for Cauliflower Au Gratin

You only need a few main ingredients that taste beyond amazing together. Here is everything you need to make this amazingly creamy Cauliflower Au Gratin:

• Fresh Cauliflower florets- the main ingredient! Cauliflower is the perfect veggie to deliver creamy, cheesy goodness straight to you.
• Butter + Onions – butter is used to saute the onions and make a roux. While the subtle flavor of onions makes a great base for any casserole dish.
• All-purpose Flour – this creates a roux, which is a much more stable sauce for leftovers.
• Whole Milk + Heavy Cream – both are used here to thin out the sauce but still keep it nice and creamy.
• Cheddar Cheese – delicious sharp cheddar cheese tops this whole dish. For the best melting results, buy a block and shred the cheese yourself.
• Nutmeg, Salt + Black Pepper – Nutmeg is a classic ingredient for a roux and salt and pepper keep this seasoned well.

Variations

Before making this recipe, consider these variations to take your Cauliflower Au Gratin to the next level!

• Bacon – I am a firm believer that bacon makes everything taste better. Simply cook bacon, chop into pieces and drain most of the fat. Omit the butter and sauté the onions. Then proceed as normal!
• Toppings – you can add chips or just about any other crunchy topping. French fried onions, Ritz crackers, Panko breadcrumbs, corn flakes, sour cream and onion chips, etc.. Feel free to switch it up based on what you have on hand.
• Using Different Cheeses– while cheddar cheese is a great, all-purpose cheese, try using parmesan cheese, gruyere cheese, blue cheese or even goat cheese for a new and interesting flavored Cauliflower au Gratin.
• Gluten-Free: Substitute all-purpose flour with a gluten-free alternative and use gluten-free panko breadcrumbs for the topping.
• Spice It Up: Add a pinch of cayenne pepper or garlic powder for a kick.

How to Make Cauliflower Au Gratin

Really simple recipe steps here. It may seem like a lot of steps but rest assured this is much easier to make than you think. For full recipe details, including ingredient measurements, scroll down to the printable recipe card at the bottom of this post. Here are my step by step directions for making this dish:

1. Preheat Oven + Prep Veggies

Preheat oven to 400° F. Chop up your onions and cauliflower into bite-sized pieces.

2. Steam Cauliflower

Steam chopped cauliflower until fork tender. Drain really well. Place into buttered baking dish and set aside.

Pro Tip: Make sure your cooked cauliflower is well-drained to avoid a watery sauce.

3. Sauté + Brown the Onions

While cauliflower is cooking, melt butter over medium heat in deep cast iron skillet. Sauté onions until tender and golden brown, 5-7 minutes. Be sure to get them really brown! That is where a lot of this flavor comes from.

4. Make a Roux

Whisk in the flour to make a roux, and cook for 1-2 minutes. Next, Whisk in the milk. Season with salt, black pepper and nutmeg. Remove from heat and stir in the heavy cream. Then finally, pour it over steamed cauliflower in the prepared baking dish.

5. Bake

Top with cheese and bake 15 minutes. Serve hot.

Storage + Make Ahead Directions For Cauliflower Au Gratin

Allow leftovers to cool to room temperature. Transfer to an airtight container and store in the fridge for up to 3 days. Reheat in a medium saucepan over low heat or in the oven until warmed through.

To Freeze: Assemble the dish, but don’t bake it. Wrap it tightly in plastic wrap and foil, and store in the freezer for up to 3 months. When ready to bake, thaw it in the fridge overnight and bake as directed.

To Make Ahead: Prepare the dish up to the baking step and store it in an airtight container in the fridge for up to two days. Bake when ready to serve.

More Cauliflower Recipes to Try!

Looking for even more cauliflower recipes? Here are some!

• Roasted Cauliflower
• Creamy Cauliflower Soup
• Grandma’s Cheesy Cauliflower
• Cauliflower Cheese Sauce for Pasta
• Cauliflower Fried Rice

This Cauliflower Au Gratin is the perfect side dish that’s sure to become a family favorite. Whether you’re cooking for a holiday meal or just need a comforting cheesy casserole, this recipe has you covered! The printable recipe card is below. Have a great day, friends!

If you make this recipe, I would really appreciate it if you would give it a star rating and leave your review in the comments! If you have a picture of your finished dish, post it on Instagram using the hashtag #laurenslatest and tagging me @laurens_latest.