Cauliflower au Gratin

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Cauliflower au Gratin is a creamy veggie dish with roasted cauliflower in a rich cheesy sauce.

This cauliflower side dish is perfect alongside a roast dinner, and great with almost any cheese in your fridge!

cooked Cauliflower au Gratin in the dish with some taken out

What is Cauliflower au Gratin?

A gratin is a method of making a baked dish or casserole that’s covered in breadcrumbs and/or cheese and browned. We often think of Potatoes Au Gratin but it’s great for all kinds of vegetables including brussels sprouts, zucchini, spinach, and more!

In this recipe, the cauliflower is roasted (adding another layer of flavor) which keeps it from getting watery. The sauce is homemade but it’s easy to make and so rich!

Why You’ll Love This

  • Super rich and super cheesy, it tastes amazing!
  • Roasting cauliflower adds flavor while keeping it perfectly tender-crisp.
  • The cheese sauce is great with any cheese that you have on hand.
  • This dish is low carb and high in flavor.
  • This cozy dish can be made ahead of time and baked before serving.

ingredients for cauliflower au gratin

Ingredients

CAULIFLOWER: Choose a large head that is free of brown spots. Short on time? Use a fresh bag of pre-washed and pre-cut cauliflower.

This recipe does work with frozen cauliflower as well, be sure to drain it very well after cooking so the sauce doesn’t get watery.

SAUCE: This sauce uses milk in place of cream and cream cheese gives it an extra rich flavor and texture.

CHEESE: Sharp cheddar adds great flavor. I love to use a little bit of Gruyere or swiss cheese as well. If you’re not a fan of swiss cheese, use all cheddar or another type of cheese.

Variations

For a colorful vegetable au gratin, mix broccoli florets with the cauliflower or add a medley of veggies like zucchini, onions, or leeks to the roasting pan. Or add diced chunks of ham, cooked chicken, or bacon for a heartier main dish casserole.

cooked cauliflower on a baking sheet to make Cauliflower au Gratin

How to Make Cauliflower au Gratin

  1. Roast: Roast seasoned cauliflower until tender.
  2. Make Sauce: While cauliflower is roasting, make a roux & whisk in milk (per the recipe below). Cook until bubbly.

adding cheese to a dish

  1. Add Cheese: Stir in remaining ingredients (except for ¼ cup cheddar cheese). Whisk & simmer until smooth.
  2. Bake: Combine the sauce with the roasted cauliflower and bake in a casserole dish.

Cauliflower au Gratin in the casserole dish before baking

Tips for Perfect Gratin

  • Roasting the cauliflower keeps the sauce from getting watery. If you steam or boil (or use frozen) be sure to drain very well.
  • Broccoli can be added to the cauliflower if desired.
  • The sauce is very rich, ensure your cauliflower head is at least 7-8 cups.
  • Remove the sauce from the heat before stirring in the cheese. If the cheese overheats or boils it can separate.
  • The cheese on top can be replaced with buttery bread crumbs. Combine 1/3 cup breadcrumbs with 1 tablespoon melted butter and sprinkle over top before baking.

top view of cooked Cauliflower au Gratin in the dish

Storing Leftovers

Keep leftover cauliflower au gratin in a covered container in the fridge for up to 4 days.

More Cheesy Sides

Did your family love this Cauliflower au Gratin? Leave us a rating and a comment below! 

close up of cooked Cauliflower au Gratin
4.89 from 35 votes
Review Recipe

Cauliflower au Gratin

Prep Time 20 minutes
Cook Time 45 minutes
Total Time 1 hour 5 minutes
Servings 8 cups
Cauliflower au Gratin is a creamy & cheesy side dish, baked until perfectly golden!

Ingredients

  • 8 cups cauliflower florets about 1 large head
  • 2 tablespoons olive oil
  • salt & pepper to taste

Sauce

  • 2 tablespoons butter
  • 2 tablespoons all-purpose flour
  • 2 cloves garlic minced, optional
  • 1 cup milk
  • 4 ounces cream cheese softened
  • ¼ teaspoon salt or to taste
  • ¼ teaspoon black pepper
  • ½ teaspoon dry mustard powder
  • 1 cup sharp cheddar cheese shredded & divided
  • ½ cup Gruyere or swiss cheese shredded, or additional cheddar

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Instructions

  • Preheat oven to 400°F.

Roast Cauliflower

  • Rinse cauliflower and break into bite-sized florets. Toss with olive oil and salt and pepper to taste.
  • Place on a baking sheet and roast 15-20 minutes or until tender.

Make Sauce

  • While cauliflower is roasting, melt butter (and garlic if using) in a saucepan until fragrant, about 30 seconds. Whisk in flour until smooth and let cook for 1 minute. Add milk a little at a time while whisking until smooth.
  • Cook over medium heat until thick and bubbly. Stir in cream cheese, salt, black pepper, and mustard powder until smooth. Add in ¾ cup cheddar cheese and swiss cheese. Whisk until smooth.

Bake

  • Toss cheese mixture with roasted cauliflower and place in a 2 qt casserole dish. Top with remaining cheese and bake 20-25 minutes or until heated through.
  • Broil 1-2 minutes or until browned.

Recipe Notes

Roasting the cauliflower keeps the sauce from getting watery. If you steam or boil (or use frozen) be sure to drain very well.
Broccoli can be added to the cauliflower if desired.
The sauce is very rich, ensure your cauliflower head is at least 7-8 cups.
Remove the sauce from the heat before stirring in the cheese. If the cheese overheats or boils it can separate. 
The cheese on top can be replaced with buttery bread crumbs. Combine 1/3 cup breadcrumbs with 1 tablespoon melted butter and sprinkle over top before baking.
Leftovers can be stored in an airtight container in the refrigerator for up to 4 days.

Nutrition Information

Serving: 1cup, Calories: 251, Carbohydrates: 8g, Protein: 9g, Fat: 21g, Saturated Fat: 11g, Polyunsaturated Fat: 1g, Monounsaturated Fat: 7g, Trans Fat: 1g, Cholesterol: 53mg, Sodium: 304mg, Potassium: 306mg, Fiber: 2g, Sugar: 4g, Vitamin A: 621IU, Vitamin C: 35mg, Calcium: 226mg, Iron: 1mg

(Nutrition information provided is an estimate and will vary based on cooking methods and brands of ingredients used.)

Course Side Dish
Cuisine American
cooked Cauliflower au Gratin with a spoon and a title
close up of Cauliflower au Gratin in the dish with a title
ingredients to make Cauliflower au Gratin with writing
ingredients to make Cauliflower au Gratin with cooked dish full and a title
About the author

Holly

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Holly is a wine and cheese lover, recipe creator, shopping enthusiast and self appointed foodie. Her greatest passion is creating in the kitchen and making deliciously comforting recipes for the everyday home cook!

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Recipe Rating




Comments

  1. This cauliflower au gratin is so so cheesy, flavorful, and delicious! The perfect healthy twist on the ultimate comfort food.5 stars

  2. I made this for our Thanksgiving feast and everyone loved it! Roasting the cauliflower adding some delicious smoky flavor too.5 stars

  3. Fantastic! I love cauliflower and I usually eat it just roasted with olive oil and herbs but your recipe just opened my eyes to another level of deliciousness. I’ll be making this over and over again.5 stars

  4. My family made this dish disappear in record time! It’s so perfectly gooey and cheesy. The cream cheese makes the sauce so rich and silky! Loved it!5 stars

  5. For someone like me who is slowly transitioning into keto and low carb, this recipe is going to help tremendously! I am so happy that you use cauliflower to make this gratin.5 stars

    1. I have only made this as written but you can leave it out if you’d like. This will change the flavor and texture as the cream cheese helps to thicken and adds a bit of a tangy richness to the sauce.

    2. I’m always looking for new ways to make cauliflower and this gratin was great! Can’t go wrong with 3 kinds of cheese.5 stars

  6. Making this for Thanksgiving! Can I assemble the day before and then bake the next? Want to have it ready to go but didn’t know if the cheese sauce would get werid.

    Thanks!

  7. THIS RECIPE WAS FANTASTIC !

    My head of cauliflower had only 4-5 cups ! I am so glad I measured and halved the sauce ingredients. Had to use a tiny bit more milk to adjust for my liking but overall it turned out fantastic!!!!

    Thanks again for a great recipe5 stars

  8. Made this last night and it was delicious! Great leftovers too. Perfect substitute for “mash” in a low carb bangers’ n’ mash dinner5 stars

  9. Hi Holly,
    It’s been a miserably wet Saturday here in Germany where I live. But I should maybe point out that I am in fact English, but with dual nationality. I am diabetic and am pretty long in the tooth now, don’t drink, don’t smoke and am long since a pensioner and even longer divorced.
    So, me and my beloved PC here spend a fair amount of hours trawling the net for recipes that suit my circumstances. And today I had the good fortune to stumble across this – for the want of a better word, ‘down to earth’, your web site with dishes very reminiscent of those that ‘Mum’ used to make.
    I do look for low-carb and low fat dishes ‘cos I now longer have a youthful figure :o(.
    One thing that I cannot do though is to ‘Meal plan’ – I have good intentions when I shop, but these very rarely come to fruition and I end up eating out far too often.
    But that is far too much about my problems. Another thing that has struck me about your website is your youthful looks – are you really telling the truth that you have a 28 year old daughter – sister I could believe! So if your recipes can do that for you – I want some of them!
    Sorry to have gabbled on for so long, but please, keep up with the good work and recipes.
    Very best regards to you and your family.
    Derek Cridland.

    1. I’m so glad you’ve loved the recipes Derek! Thank you so much for your kind words (and yes, I have an almost 29 year old!!). :) Happy Cooking.

  10. The receipt calls for 1 cup of milk. It wasn’t enough as the roux was way too thick. I would use 1 1/2 to 2 cups. A.so, ingredients called for garlic but I didn’t see on the instructions when to add.
    Maybe I missed?1 star