Brussels Sprouts Gratin

Need a classy but easy side? Try this Brussels sprouts gratin. Made with blanched sprouts in a rich Gruyere sauce, it’s studded with diced pancetta for an extra bump of flavor.

By
Elise Bauer
Elise Bauer
Elise Bauer
Elise founded Simply Recipes in 2003 and led the site until 2019. She has an MA in Food Research from Stanford University.
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Updated October 27, 2023
Elise Bauer
Brussels Sprouts Gratin
Elise Bauer

Tick tock, tick tock. Turkey day is around the corner, are you ready? Somehow Thanksgiving just doesn't seem the same without at least one classic, cheesy gratin.

Scalloped potatoes or turnips often make an appearance here, and some years, a gratin of fennel was the star.

Brussels Sprouts Gratin
Elise Bauer

This year my gratin of choice is a creamy Brussels sprouts gratin, with sprouts that have been blanched and then baked in a sauce with pancetta, shallots, and Gruyere.

How to Choose Brussels Sprouts

Brussels sprouts' appearance in the markets is a sign of cooler weather and holidays to come. When shopping for them, look for compact little heads that are bright green and firm. Regardless of weather or not they are on the stem, they should be heavy for their size and the leaves tightly packed. Avoid yellowing or wrinkles leaves, if possible (since that shows age). Any black spots are a sign of fungus.

Smaller ones are more tender and sweeter. They are good for cooking whole. Larger ones are easier to work with when cutting them in half, especially since we blanch them in advance of baking in this recipe.

Can This Brussels Sprouts Dish Be Vegetarian?

It's easy to make this a vegetarian dish! Just remove the pancetta and add an extra tablespoon of butter. You can also swap the pancetta out with mushrooms, thinly sliced zucchini or even some thinly sliced carrots (which will add a bit of sweetness to the gratin).

Other Cheeses to Try in a Brussels Sprouts Gratin

Here are a few other cheeses to try in place of Gruyere:

  • Gouda
  • Emmental
  • Jarlsberg
  • Raclette
  • Edam
  • Cheddar

How to Make This Brussels Sprouts Gratin in Advance

If you're getting ready for a big dinner party or a holiday feast, you can make this dish the day before. Just prepare all of the ingredients in a baking dish, cover and refrigerate. Then, remove from the fridge, preheat the oven to 400°F and just bake as directed, adding a little extra time since the casserole will be going in cold. Voila! Easy cheesy Brussels sprouts!

More Cheesy Side Dishes You’ll Love

From the Editors Of Simply Recipes

Brussels Sprouts Gratin

Prep Time 20 mins
Cook Time 60 mins
Total Time 80 mins
Servings 6 to 8 servings

The best way to trim the brussels sprouts is to slice off 1/4 inch from the bottom stem end with a paring knife. This will make it easier to peel off any tough outer leaves. Then, when cutting the brussels sprouts in half, place them cut-side down on the cutting board to help stabilize them.

You can easily make this dish vegetarian by leaving out the pancetta in Step 2. Just add an additional tablespoon of butter in Step 3.

Ingredients

  • 2 pounds brussels sprouts, trimmed of outer leaves and sliced in half

  • Salt, to taste

  • 2 ounces pancetta, diced

  • 1 tablespoon butter

  • 3 shallots, peeled, halved, and sliced

  • 2 tablespoons all-purpose flour

  • 1 3/4 cups whole milk

  • 1 scant pinch freshly ground nutmeg

  • Thyme leaves from 2 sprigs or 1/2 teaspoon dry thyme

  • 4 ounces grated Gruyere cheese, divided

Method

  1. Preheat oven and prepare baking dish:

    Preheat the oven to 400°F. Butter an 8 x 12-inch gratin or casserole dish.

  2. Blanch the Brussels sprouts:

    Fill a large pot with 4 quarts of water plus 1 tablespoon salt. Bring to a boil. Add the halved Brussels sprouts and blanch for 3 to 4 minutes, until just barely tender. Remove from heat. Drain in a colander and rinse with cold water to stop the cooking. Set aside.

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    Elise Bauer
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    Elise Bauer
  3. Brown the pancetta and render the fat:

    Place diced pancetta in a large pot on medium low heat. Cook until most of the fat is rendered, about 8 to 10 minutes. Remove the pancetta from the pan and set aside, leaving the rendered fat in the pan.

    brussels-sprouts-gratin-method-3a
    Elise Bauer
  4. Sauté shallots:

    Add butter to the pot and melt on medium heat. Add the shallots and gently cook until softened, about 4 to 5 minutes.

    brussels-sprouts-gratin-method-4
    Elise Bauer
  5. Make roux:

    Add the flour to the butter shallot mixture. and whisk for 1 to 2 minutes.

    brussels-sprouts-gratin-method-5
    Elise Bauer

    Slowly add the milk while stirring with a wooden spoon until the roux is incorporated into the milk.

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    Elise Bauer

    Cook over medium low heat for several minutes, stirring until the sauce thickens and coats the back of your spoon. Add fresh thyme and sprinkle with nutmeg.

  6. Add cheese, then half of the pancetta to white sauce:

    Add 3 ounces of grated Gruyere cheese into the white sauce and stir until the cheese is melted and incorporated into the sauce. Add half of the cooked pancetta back to the sauce. Taste and add more salt, if necessary.

    brussels-sprouts-gratin-method-8
    Elise Bauer
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    Elise Bauer
  7. Add Brussels sprouts, transfer to gratin dish, prepare, and bake:

    Add the Brussels sprouts into the cheese sauce and toss to coat. Transfer the cheesy Brussels sprouts into the prepared casserole or gratin dish. Sprinkle with the remaining pancetta and the remaining 1 ounce of grated Gruyere cheese.

    brussels-sprouts-gratin-method-10
    Elise Bauer
    brussels-sprouts-gratin-method-11
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    Bake for 25 minutes until top is lightly browned and bubbly. Remove from oven and let sit for 10 minutes before serving.

    Did you love the recipe? Give us some stars and leave a comment below!

Brussels Sprouts Gratin
Elise Bauer
Nutrition Facts (per serving)
204 Calories
12g Fat
16g Carbs
10g Protein
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Nutrition Facts
Servings: 6 to 8
Amount per serving
Calories 204
% Daily Value*
Total Fat 12g 16%
Saturated Fat 6g 30%
Cholesterol 30mg 10%
Sodium 237mg 10%
Total Carbohydrate 16g 6%
Dietary Fiber 4g 13%
Total Sugars 6g
Protein 10g
Vitamin C 72mg 361%
Calcium 253mg 19%
Iron 2mg 10%
Potassium 529mg 11%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
Nutrition information is calculated using an ingredient database and should be considered an estimate. In cases where multiple ingredient alternatives are given, the first listed is calculated for nutrition. Garnishes and optional ingredients are not included.