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Brussels Sprouts Gratin

  • Serves: 8
  • Prep Time: 12 min
  • Cook Time: 35 min
  • Calories: 382
Brussels sprouts gratin with cream, garlic, Parmesan, Gruyere cheeses and toasted bread crumbs in a baking dish

This decadent Brussels sprouts gratin boasts loads of cream and garlic, plus it gets a super dose of cheesiness from both Parmesan and Gruyère cheeses.

A Creamy Brussels Sprouts Gratin For Thanksgiving Day, or Any Day!

Rich and creamy, this cheese-laden Brussels sprouts gratin is nothing short of over-the-top. It’s also a refreshing change for your Thanksgiving side dish line-up! After years of creamed spinach and green bean casserole, maybe you’d like to mix up your turkey day veggies. If that’s the case, say hello to Brussels sprouts au gratin! Even the most die-hard Brussels sprout skeptic will probably be won over by the sheer indulgent goodness of this delicious casserole. Plus, don’t think of this yummy side as a Thanksgiving-only recipe! It’d be a Christmas dinner superstar, or really a welcome side dish for almost any meal you can imagine, particularly on a dreary winter day. You could even argue that you need this gratin even more on a random weeknight in January than you do during the holidays.

ingredients laid out for Brussels sprouts gratin, cream, leeks,  garlic, Parmesan, Gruyere cheeses and bread crumbs.
sautéed leeks and shaved brussels sprouts in a baking dish
Cream, garlic, Parmesan, Gruyere cheese, fresh thyme and nutmeg in a pan for brussels sprout gratin
Cream, garlic, Parmesan, Gruyere cheese, fresh thyme, nutmeg and dijon mustard in a pan for brussels sprout gratin

All The Ingredients You’ll Need To Make Our Brussels Sprouts Gratin Recipe

Instead of onions, we’re using leeks, which are mild and sweet and a classic gratin ingredient. Their sweetness pairs wonderfully with the slight sharpness of Brussels sprouts—they’re a brassica, after all, and they’ve got just a hint of bitterness. Heavy cream softens that bitterness too, and cheese...well, cheese makes everything better. Especially when that cheese is nutty, savory Gruyère. Here’s all you’ll need to make the best Brussels sprouts gratin, ever:

  • Brussels sprouts
  • Leeks
  • Garlic
  • Olive oil
  • Heavy cream
  • Gruyère cheese
  • Parmesan
  • Fresh thyme
  • Nutmeg
  • Panko breadcrumbs
leeks and brussel sprouts in a pan with Cream, garlic, Parmesan, Gruyere cheese, fresh thyme, nutmeg and dijon
Brussels sprouts gratin with cream, garlic, Parmesan, Gruyere cheeses and toasted bread crumbs in a baking dish
Brussels sprouts gratin with cream, garlic, Parmesan, Gruyere cheeses and toasted bread crumbs in a baking dish
Brussels sprouts gratin with cream, garlic, Parmesan, Gruyere cheeses and toasted bread crumbs in a baking dish

How To Make Brussels Sprouts Au Gratin

Take your favorite vegetable and bathe it in a cheese-and-heavy cream sauce. Top with the most airy, the most crispy breadcrumbs. Bake. Serve. Enjoy the afterglow. That’s pretty much how this gratin recipe goes! It really is that easy. We’ll give you a few tips for making sure this recipe turns out perfect:

  1. For shredding the sprouts, you can often buy them pre-shredded, use a mandoline slicer, or you can use the shredding attachment on your food processor. Or, just a sharp knife will also do the trick.
  2. Spring for real Gruyère, if you can. We are only calling for four ounces, and real Gruyère has an absolutely unmatched salty, nutty flavor. It really makes the whole dish.
  3. Don’t skip the seasonings! The nutmeg and fresh thyme are tiny additions that add major complexity to a relatively simple recipe. Nutmeg especially adds a unique warmth to the finished dish that we just adore.
  4. This Brussels sprouts gratin isn’t great for making ahead, but you *can* do the fussy prep work ahead of time and make your day-of workload a little lighter. If you want to get ahead, prep the sprouts, shred the Gruyère and grate the Parmesan a day ahead of time and store them in the fridge until you’re ready to go.
Brussels sprouts gratin with cream, garlic, Parmesan, Gruyere cheeses and toasted bread crumbs in a baking dish

Tools You’ll Need

More Thanksgiving Brussels Sprouts Recipes To Try

It looks like we love Brussels sprouts. Probably because we do! This is the fifth Brussels sprout recipe we’ve shared so far, and hey, we’re just getting started! If you’re in love with these tiny buds of goodness, too, give some of these recipes a try:

Brussels sprouts gratin with cream, garlic, Parmesan, Gruyere cheeses and toasted bread crumbs in a baking dish

Thanksgiving Side Dish Planning Starts Now!

Just kidding—TBH we started thinking about Thanksgiving back in August. But we’re in full swing now! It’s the food lovers holiday, after all. If this recipe makes it onto your Thanksgiving table—or even just your dinner table!—we’d love to know. Share a photo and tag us on Instagram using @themodernproper and #themodernproper so that we can see your stuff! Happy eating!

Brussels Sprouts Gratin

  • Serves: 8
  • Prep Time: 12 min
  • Cook Time: 35 min
  • Calories: 382

Ingredients

  • 5 tbsp Olive oil
  • 3 cups Thinly sliced leeks, (3 large leeks) white and light green parts only
  • 4 Garlic cloves, minced
  • 1 pound Brussels sprouts, ends trimmed, shredded
  • 2 cups Heavy cream
  • 4 oz Gruyère cheese, grated
  • 1/2 cup Grated parmesan cheese
  • 1 tsp Kosher salt
  • 1/2 tsp Freshly cracked black pepper
  • 2 tsp Minced, fresh thyme
  • 1/4 tsp Nutmeg
  • 1 cup Panko

Method

  1. Preheat the oven to 425°F. Grease a 9x13 baking dish with cooking spray or butter, set aside.
  2. In a large skillet, heat 2 tablespoons olive oil over medium heat. Add the leeks to the pan and cook for 4 minutes. Add the garlic and cook for 1 minute longer.
  3. Transfer the leek mixture into a large bowl along with the shredded brussels, toss to combine.
  4. Using the same skillet, add the cream, Gruyere, 1/4 cup parmesan, salt, pepper, thyme and nutmeg. Bring to a simmer stirring continuously until cheese melts and a thick sauce is achieved, about 3 minutes.
  5. Pour the sauce over sprouts and leeks and toss to coat.
  6. Transfer the sprouts mixture into the prepared 9x13 baking dish. Place it in the oven on the center rack for 20 minutes.
  7. In a small bowl, combine the panko with remaining 1/4 cup parmesan and remaining 3 tablespoons of oil.
  8. Scatter bread crumb mixture over sprouts and return to oven until golden brown, 5 to 8 minutes.