This cauliflower gratin with caramelized leeks and pecans is a creamy, savory side dish made with Gruyère, Parmesan, heavy cream, and a touch of nutmeg. The tender cauliflower is baked until golden, then topped with sweet, balsamic-glazed leeks, while ground pecans add richness and subtle texture. Naturally gluten-free and low-carb, it’s an elegant yet comforting side dish for the holidays or any special meal.
Cauliflower may be an everyday staple in a low-carb kitchen, but this gratin makes it feel special enough for a holiday table. I originally created the recipe at my sister’s request for her holiday preparations, combining cauliflower with Gruyère, Parmesan, pecans, and slowly caramelized leeks.
The gratin itself is very simple to prepare. The cauliflower is briefly boiled so it remains slightly firm, then baked in a creamy Gruyère and pecan sauce until tender and golden.
Caramelized leeks make the difference
The leeks require a little attention, but they are what elevate this dish. Cooking them slowly allows their natural sweetness to develop, while a small amount of balsamic vinegar adds depth and balances the richness of the cream and cheese.
As the leeks begin to stick and leave browned areas on the pan, add water just one teaspoon at a time. This helps release the flavorful browned bits while allowing the leeks to soften and caramelize without using too much oil.
Because the leeks take approximately the same amount of time as the gratin, you can prepare them while the cauliflower is baking. They are added during the final five minutes, preserving some of their texture and keeping them visible on top.
A naturally gluten-free gratin
This cauliflower gratin is naturally gluten-free because the sauce contains no flour. It will remain creamy rather than becoming very thick. If you prefer a thicker, more cohesive sauce, stir in two teaspoons of arrowroot or tapioca starch dissolved in a little cold water before pouring it over the cauliflower.
Serve the gratin warm alongside roasted chicken, turkey, beef, or lamb. It also works beautifully as part of a vegetarian holiday spread.
For another easy recipe with cauliflower, you should try my Whole Roasted Cauliflower with Pesto.
*This post contains affiliated links, which means I get a small commission if you choose to purchase something via one of my links, at no extra cost to you.
Print
Cauliflower Gratin with Caramelized Leeks and Pecans
- Prep Time: 20 minutes
- Cook Time: 40 minutes
- Total Time: 1 hour
- Yield: 6
- Category: Side Dish
- Method: Baking
- Cuisine: French
- Diet: Gluten-Free, Low-Carb, Vegetarian
Description
This cauliflower gratin with caramelized leeks and pecans is a creamy, savory side dish made with Gruyère, Parmesan, heavy cream, and a touch of nutmeg. The tender cauliflower is baked until golden, then topped with sweet, balsamic-glazed leeks, while ground pecans add richness and subtle texture. Naturally gluten-free and low-carb, it’s an elegant yet comforting side dish for the holidays or any special meal.
Ingredients
- 1 large head cauliflower, washed, patted dry, and cut into large florets
- 2/3 to 1 cup (160–240 milliliters) organic heavy cream
- 3 ounces (85 grams) Gruyère cheese, grated
- 1/2 cup (approx 55 grams) ground pecans, preferably dry-roasted
- A pinch of ground nutmeg
- Salt and freshly ground black pepper, to taste
- A handful of grated Parmigiano Reggiano, for topping
- 2 large leeks
- Avocado oil or extra virgin olive oil
- 2 teaspoons good-quality balsamic vinegar
Instructions
- Preheat the oven to 375°F (190°C).
- Bring a pot of water to a boil. Add the cauliflower and cook for 5 to 7 minutes, depending on the size of the florets. The cauliflower should remain firm, as it will continue cooking in the oven.
- Drain the cauliflower thoroughly and arrange it in a 9-by-9-inch (23-by-23-centimeter) baking dish or another baking dish of a similar capacity.
- Combine the heavy cream, Gruyère, ground pecans, nutmeg, salt, and pepper. Pour the mixture evenly over the cauliflower, then sprinkle the Parmigiano Reggiano on top.
- Bake for 25 to 30 minutes, or until the cauliflower is tender and the top begins to turn golden.
- While the gratin is baking, prepare the leeks. Cut them in half lengthwise and clean them thoroughly, making sure there is no soil trapped between the layers. Pat dry and thinly slice the white and light green portions.
- Heat a small amount of avocado or olive oil in a large sauté pan over low to medium heat. Add the leeks and cook slowly, stirring whenever they begin to stick.
- When browned spots form on the bottom of the pan, add about 1 teaspoon of water and stir to release them. Continue cooking, stirring frequently and adding water 1 teaspoon at a time as needed, until the leeks are soft and caramelized, about 25 minutes.
- Add the balsamic vinegar, stir well, and remove the pan from the heat.
- Spoon the caramelized leeks over the cauliflower gratin. Return the dish to the oven and bake for 5 more minutes. Serve warm.
Notes
For the best flavor, lightly dry-roast the pecans before grinding them.
The flourless sauce will be creamy but relatively loose. For a thicker sauce, dissolve 2 teaspoons of arrowroot or tapioca starch in a small amount of cold water and mix it into the cream mixture.
Use only the white and tender light green portions of the leeks. The dark green leaves can be reserved for making stock.
An aged, slightly thick balsamic vinegar works especially well with the caramelized leeks.
8 Comments
Sherry
January 22, 2023 at 4:58 pmHi Claudia,
I made it tonight. It’s very delicious. The only thing I wasn’t sure about it was the heavy cream. I added a cup of heavy cream and it didn’t evaporate nor didn’t get thick. Is it the way it’s supposed to be?
Thank you kindly!
Claudia
January 23, 2023 at 7:37 amHi Sherry, thank you so much for your feedback. It might also depend on the type of cream, but next time, if you want it to get thicker and more creamy, add one or two teaspoons of tapioca flour dissolved in a little bit of cold water (mix this liquid with the cream before adding it to the casserole). I hope this helps xx
Jodi
February 1, 2019 at 11:01 amMmmmm this looks lovely. I am very new to the lectin free diet so I wonder… how is heavy cream lectin free?
I understand I could use coconut milk but am very curious about a lectin free heavy cream. I will try this recipe this weekend for sure! Thank you. Jodi
Claudia
February 2, 2019 at 11:20 amHi Jodi, I recommend you read The Plant Paradox book, it will help you understand all the “why”s and will make it easier for you to implement PP in your life. The thing is, is not all about lectins. The reason we avoid certain dairy products is because they have a protein called Casein A1, which is not healthy for us (as opposed to Cassein A2 which is easier for us to digest). Heavy cream is mostly fat, so no protein, so no casein A1, so acceptable in moderation (small quantities). Look for an organic and / or grass fed brand.
Jodi
February 2, 2019 at 11:36 amThanks so much Claudia! I listened to The Plant Paradox audio book a couple of weeks ago. I remember the casein A1 part but missed the part about cream not having protein. I have ordered the book on Amazon to take a better look and get a better understanding. I can’t wait to try this recipe. I will let you know how it goes. I want to try so many of your recipes!!
Claudia
February 3, 2019 at 2:30 pmYes, reading and being able to highlight and review certain parts will help a lot. I had to re-read several times to remember everything. Let me know if you make anything. xx
grace
January 5, 2019 at 6:25 pmON THE RICH SIDE BUT YUMMY.
Thanks for another keeper Claudia
Claudia
January 6, 2019 at 10:52 amThank you Grace, glad you loved it. Yes, a little gourmet, that’s why is more like a holiday dish :D. xx