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Roasted Brussels Sprouts Gratin

5 from 5 votes
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Pretty sure if you hate brussels sprouts, you haven't had them the right way. This roasted brussels sprouts gratin with garlic crumble and fried onion topping is going to elevate your side dish game at any party or potluck AND you will fall in love with brussels sprouts all over again! PROMISE!

Pretty sure if you hate brussels sprouts, you haven't had them the right way. This roasted brussels sprouts gratin with garlic crumble and fried onion topping is going to elevate your side dish game at any party or potluck AND you will fall in love with brussels sprouts all over again! PROMISE!

If roasted garlic brussels sprouts did not change your mind about brussels sprouts, then hopefully this roasted brussels sprouts gratin with garlic crumble and crispy onion topping will.

Brussels sprouts are legit one of my favorite vegetables of all time. We have roasted brussels sprouts as least once a week and it’s always on my shopping list. I feel like those that despise them are just scarred from having a bad experience (re: boiled). You’ve gotta give this one a shot. The topping itself is WORTH IT.

Pretty sure if you hate brussels sprouts, you haven't had them the right way. This roasted brussels sprouts gratin with garlic crumble and fried onion topping is going to elevate your side dish game at any party or potluck AND you will fall in love with brussels sprouts all over again! PROMISE!

Will you just LOOK at that gorgeous topping? Breaking into it was a little heartbreaking because it was like shattering the sugar top of creme brulee — but it also meant one step closer to having this delicious gratin on my plate.

I had extra garlic parmesan paste from my extra garlicky and cheesy bread so I mixed that with panko breadcrumbs to make the topping for this brussels sprouts gratin. But I didn’t stop there. I then used gourmet (as TJ’s would call it) fried onions and elevated the dish even more.

Pretty sure if you hate brussels sprouts, you haven't had them the right way. This roasted brussels sprouts gratin with garlic crumble and fried onion topping is going to elevate your side dish game at any party or potluck AND you will fall in love with brussels sprouts all over again! PROMISE!

GAH YOU GUYS! You just seriously have to make this. Even if it’s not for Thanksgiving; what about for like a party or potluck? Or what if you just want pure comfort food in the form of brussels sprouts and garlicky oniony goodness? Because that’s my favorite kind of party. Well, sort of. Add some form of bubbly and friends…I’m all over that sign up list!

Pretty sure if you hate brussels sprouts, you haven't had them the right way. This roasted brussels sprouts gratin with garlic crumble and fried onion topping is going to elevate your side dish game at any party or potluck AND you will fall in love with brussels sprouts all over again! PROMISE!

I wasn’t expecting this dish to be that awesome but since it is, I think this is THE dish I am bringing to Thanksgiving dinner this year! To be honest, this doesn’t have to be a Thanksgiving side dish. This can be a side dish year-round because WHY NOT?! I know Thanksgiving is pretty much all about side dishes but why not make side dishes a year-round thing?

Pretty sure if you hate brussels sprouts, you haven't had them the right way. This roasted brussels sprouts gratin with garlic crumble and fried onion topping is going to elevate your side dish game at any party or potluck AND you will fall in love with brussels sprouts all over again! PROMISE!

I’m tempted to throw a side dish only party in July.

Pretty sure if you hate brussels sprouts, you haven't had them the right way. This roasted brussels sprouts gratin with garlic crumble and fried onion topping is going to elevate your side dish game at any party or potluck AND you will fall in love with brussels sprouts all over again! PROMISE!

Roasted Brussels Sprouts Gratin with Garlic Crumble and Fried Onion Topping

Pretty sure if you hate brussels sprouts, you haven't had them the right way. This roasted brussels sprouts gratin with garlic crumble and fried onion topping is going to elevate your side dish game!
5 from 5 votes
Prep Time: 35 minutes
Cook Time: 25 minutes
Total Time: 1 hour
Servings: 6
Author: Julie Chiou
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Ingredients 

  • 2 pounds (907 g) brussels sprouts, sliced in half

For the bechamel sauce:

  • 4 tablespoons (56 g) unsalted butter
  • 3 tablespoons all-purpose flour
  • 1 ⅔ cup (394 ml) whole milk, room temperature
  • Pinch ground nutmeg
  • Salt and pepper, to taste

For the garlic crumble and crispy onion topping

  • 3 cloves of garlic, minced
  • 3 tablespoons grated parmesan cheese
  • ¼ cup (59 ml) olive oil
  • 1 cup (60 g) panko breadcrumbs
  • 1 cup (236 g) or more, definitely more crispy onions

Instructions 

  • Preheat oven to 400 °F (204 °C) and place brussels sprouts onto a nonstick baking sheet. Drizzle olive oil all over then season with salt.
  • Roast for 20 minutes. Remove then set aside. Turn down the oven to 375 °F (191 °C)
  • Have on hand a 2 or 3 quart casserole dish.
  • While the brussels sprouts are roasting, begin making your bechamel sauce.
  • In a deep skillet, melt butter over medium heat then add flour, stirring and whisking until smooth.
  • Carefully add the milk and continue whisking until thickened, about 2-3 minutes.
  • Season with salt and pepper and pinch of ground nutmeg.
  • Remove from heat then add the roasted brussels sprouts to the skillet. Toss to cover brussels sprouts in the sauce.
  • Pour the brussels sprouts into the casserole dish and smooth into an even layer.
  • In a small bowl, mix together the garlic, parmesan, panko breadcrumbs, and olive oil. 
  • Using your hands, evenly sprinkle the topping all over the top of the brussels sprouts.
  • Bake for 25 minutes or until the top is browned.
  • Remove from oven and sprinkle crispy onions on top.
  • Let cool for 10-15 minutes before serving.

NUTRITION FACTS

Serving: 1 Serving | Calories: 311 kcal | Carbohydrates: 24 g | Protein: 7 g | Fat: 22 g | Fiber: 4 g | Sugar: 5 g

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The default measuring system for this website is US Customary. Unit conversions are provided for convenience and as a courtesy only. While we strive to provide accurate unit conversions, please be aware that there may be some discrepancies.

Recipe Rating




Suzanne

Sunday 28th of November 2021

I have made this for my family thanksgiving for 3 years and counting. I make it as directed and it comes out great every time! There are never leftovers!

Nicole C

Sunday 28th of November 2021

Second time I've made this for Thanksgiving. So much better than green bean casserole!

Julie Suppa

Friday 19th of November 2021

What brand of crispy onions do you use?

Julie Chiou

Saturday 20th of November 2021

I used Trader Joe's!

Sarah

Thursday 28th of November 2019

Very tasty! We enjoyed it with Thanksgiving sides as a nice change from green bean casserole.

Ines

Monday 1st of April 2019

Loved this so much! To make a quicker version I'm going to use store-bought bechamel sauce next time.

Julie Wampler

Wednesday 3rd of April 2019

So glad you enjoyed this!