Cheesy Brussels Sprouts Gratin

5 from 1 vote

This cheesy Brussels sprouts gratin is perfect for the holiday dinner table or for any occasion. It's cheesy, and tossed with a smooth Gruyere cheese sauce, and baked until perfectly melted and rich.

Prep Time25

Cook Time20

Total Time45

Course: Side Dish

Cuisine: American

Servings: people

Calories: 328kcal

Author: Tania

Equipment

Ingredients

1 ½ pounds fresh Brussels sprouts
3 cloves garlic minced
Olive oil
Salt and pepper to taste
2 tablespoons unsalted butter
2 tablespoons all-purpose flour
1 ¼ cups whole milk, warmed plus more as needed
1 ½ cups shredded or grated Gruyere cheese divided
¼ cup shredded parmesan cheese
⅓ cup cooked bacon diced

Instructions

Pre-roast the sprouts

Preheat oven to 400 degrees F.
Prep the Brussels sprouts: Trim the bottom stalk and remove any damaged outer leaves. Then, cut them in half lengthwise.
On a large sheet pan, toss the Brussels sprouts with the minced garlic, a few generous drizzles of olive oil, salt and pepper. Roast at 400F for 15-18 minutes.

Make the cheese sauce:

Meanwhile, in a medium saucepan, melt the butter over medium heat. Then, add the flour and whisk constantly for about 3 to 4 minutes, until thickened. This is called a roux. At this point, it should be a bit pale in color and smell a bit nutty.
Then, gradually add the warm milk, whisking to remove any lumps, until it starts to simmer. It will thicken as it heats up.
Add a ½ cup of the Gruyere cheese and stir until just melted. Season with salt and pepper to taste. Turn off the heat. If needed, add a little more milk if needed until desired consistency.

Assemble and bake

In a baking dish, toss the roasted sprouts with the prepared cheese sauce until evenly coated. Top with the remaining 1 cup of Gruyere cheese and the parmesan cheese.
Transfer the baking dish to a sheet pan to catch any spills, just in case.
Bake at 400 degrees F for 15-18 minutes until bubbly and golden brown on top. If desired, broil for 1-2 minutes for a deeper golden brown color.
To serve, top with the cooked bacon bits. Serve warm, and enjoy!

Notes

Grate your own cheese so it melts well. Pre-packaged grated cheese comes with extra preservatives that make it hard to melt.
Prep ahead: You can cook and crumble the bacon, trim and halve the Brussels sprouts, grate the cheese 1-2 days ahead. You can even pre-roast the sprouts 1 day before, but I’d recommend making the cheese sauce the same day for best results.
Storage: Place leftovers in an airtight container in the refrigerator for up to 3 days.
Reheating: Place any leftovers in the oven or microwave until warmed through.

Substitutions and variations:

Gruyere cheese: White cheddar, gouda or fontina.
Bacon: Sautéed pancetta (golden brown), crispy prosciutto.
Whole milk: 2 percent milk.

Disclaimer: Nutritional values (per serving) are approximates only.

Nutrition