Name: Brussel Sprouts au Gratin Recipe
Prep time: 10 min
Cook time: 35 min
Total time: 45 min
Ingredients: 16 ounces brussel sprouts; 1 ½ teaspoons kosher salt (divided); ⅛ teaspoon ground black pepper; 1 tablespoon olive oil; 2 tablespoons butter (reg. or dairy-free); ¼ cup sweet yellow onion (minced); 1 teaspoon garlic (minced); 2 ½ tablespoons all-purpose (OR 1-to-1 gluten-free flour); ¾ Nutpods original unsweetened/unflavored creamer (OR half-and-half); ¼ cup chicken broth (more, if needed to thin); 2 tablespoons parmesan cheese (shredded); 1 cup gruyere cheese (shredded)

Published on 04/01/23

by Erin Jensen

Brussels sprouts au gratin in a casserole dish.

Simple and Savory Brussel Sprout Au Gratin

Not that you needed convincing, but this recipe is proof that any dish with copious amounts of cheese will be a crowd pleaser. Mild flavored brussels sprouts pair perfectly with rich and tangy parmesan and creamy and nutty gruyere cheese. We especially love serving it for Easter, Thanksgiving and Christmas!

Love cheesy sides?

Then definitely check out our Cheesy Scalloped Potatoes, Delicata Squash au Gratin, or Goat Cheese Potatoes au Gratin.

What Is Au Gratin

Au gratin simply means that a dish is sprinkled with either cheese, breadcrumbs, or both and then is browned to create a crisply baked top. Potatoes Au Gratin is a classic dish that we absolutely love, and inspired this fun brussels sprouts version. Serve with our favorite Beef Tenderloin recipe or our classic baked ham!

Key Ingredients + Substitutions

Be sure to see the recipe card below for a full listing of ingredients, instructions, and estimated nutritional information.

brussels sprouts – A cruciferous vegetable that has a similar flavor to broccoli and becomes slightly sweet after cooking.
butter – The perfect ingredient to bring out the best flavors in the garlic and onion. Feel free to use a plant-based butter if you need to.
all-purpose flour – Feel free to substitute for gluten-free flour.
Nutpods Original Creamer – Be sure to select the unflavored variety. Or use half-and-half if dairy isn’t a concern.
parmesan cheese – A slightly fruity and nutty cheese, perfect for an au gratin dish.
gruyere cheese – Rich, creamy, and salt, this cheese has it all.

How To Cook Brussel Sprouts Au Gratin

Peeled and quartered brussels sprouts in a casserole dish drizzled with olive oil and salt and pepper.

Step 1: Drizzle them with olive oil and massage it into the brussels sprouts, making sure that it coats every inch. This ensures that they don’t dry out during the cooking process. Sprinkle with salt and black pepper and place in the oven for 20 minutes, tossing half way through.

A cast iron skillet with butter, minced onion, and minced garlic. The same skillet with the butter melted and flour added.

Step 2: While the brussels sprouts are cooking, bring a cast iron skillet to medium-high heat and add in the butter, letting it melt to coat the bottom of the skillet. Next, add in the minced garlic and yellow onion. Move everything around the skillet for 1-2 minutes or until they become soft and fragrant.

A whisk mixing in flour to the onion, butter, and garlic mixture.

Step 3: Add flour and use a whisk to combine it with the butter to create a paste. Continue whisking while adding the creamer and then the broth, approximately a quarter cup at a time. If it feels too thick, add another splash or two of the broth and stir.

Roux with gruyere cheese being whisked in.

Step 4: Remove the sauce from the heat and add in the shredded parmesan and half a cup of the gruyere. Stir the cheese mixture until it has all melted, take a taste, and adjust the salt and pepper as needed.

Pro Tip

We get that pre-shredded cheese is super convenient, but it also contains additives to keep it from clumping, which in turn, decreases its gooey-ness level once cooked. For the ultimate melty cheese, take the extra effort to shred your own using a cheese grater or the grater attachment on a food processor.

Roasted brussels sprouts in a casserole dish.

Step 5: Remove the brussels sprouts from the oven and check to see that they have slightly browned on the outside and are tender on the inside.

Cheese mixture poured over the top of the roasted brussels sprouts.

Step 6: Now pour your cheesy sauce over the top of the cooked brussels sprouts.

Remaining guryere cheese sprinkled on top of the cheese mixture.

Step 6: Sprinkle the remaining gruyere cheese on top and place back in oven for 8-10 minutes to ensure that they cheese melts all the way through.

Fully cooked and broiled brussels sprouts au gratin in a casserole dish.

Step 7: Move under the broiler for 1-3 minutes to get that nice slightly browned top layer. The broiler still works even with the oven door slightly open so that you can keep an eye on the browning process.

A spoonful of brussels sprouts au gratin pulling away from the casserole dish.

Step 8: Remove the au gratin brussel sprouts from the oven and let cool for 10 minutes before serving.

What To Serve With Brussel Sprouts Au Gratin

This easy side dish is here to elevate any main course. Some of our favorites are smoked ham, grilled steak, or our ultimate smoked turkey. And since it’s the season for loading up the table with our favorite sides, be sure to check out our favorite Thanksgiving side dishes for more menu inspriation.

Made this recipe and loved it?!

We would love it if you would take a minute and leave a star rating and review – it is also helpful if you made any substitutions or changes to the recipe to share that as well. THANK YOU!

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