Brussels Sprouts Gratin

Brussels sprouts blanched and baked in a cheesy white sauce with pancetta and gruyere. A perfect Thanksgiving side!

The best way to trim the brussels sprouts is to slice of 1/4-inch from the bottom stem end with a paring knife. This will make it easier to peel off any outer tough 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.

  • Prep time: 20 minutes
  • Cook time: 1 hour
  • Yield: Serves 6 to 8.

Ingredients

  • 2 pounds brussels sprouts, trimmed of outer leaves and sliced in half
  • Salt
  • 2 ounces pancetta, diced
  • 1 Tbsp butter
  • 3 shallots, peeled, halved, and sliced
  • 2 Tbsp all purpose flour
  • 1 3/4 cup whole milk
  • 1 teaspoon salt
  • Scant pinch of freshly ground nutmeg
  • Thyme leaves from 2 sprigs of thyme or 1/2 teaspoon dry thyme
  • 4 ounces of grated Gruyere cheese, divided 3 ounces and 1 ounce

Method

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1 Heat a large pot of salted water, 4 quarts of water, 1 Tbsp salt. Blanch the halved brussels sprouts for 3 to 4 minutes, until just barely tender. Remove from pot, drain, rinse with cold water to stop the cooking, set aside.

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2 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, set aside, leaving the rendered fat in the pan.

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3 Add butter to the pot and melt on medium heat. Add the shallots and gently cook until softened, about 4 to 5 minutes.  Add the flour to the butter shallot mixture to make a roux, whisk for 1 to 2 minutes. Add the milk and stir with a wooden spoon until the roux is incorporated into the milk. 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.

4 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.

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5 Preheat oven to 400°F. Butter an 8"x12" gratin dish or casserole . Add the brussels sprouts into the cheese sauce. Transfer the cheesy brussels sprouts into the casserole or gratin dish. Sprinkle with the remaining pancetta and the remaining 1 ounce of grated Gruyere cheese. Bake for 25 minutes until top is lightly browned and bubbly. Remove from oven and let sit for 10 minutes before serving.

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Comments

  1. Mollie

    How do you think this would turn out if I used frozen brussel sprouts instead? Follow the same steps like Step 1 and just check if they are tender? This looks delicious!

    • Elise

      Should work! Let me know if you try it using frozen brussels sprouts and if so, how well they work in the recipe for you.

      • Anne

        Frozen brussels sprouts worked really well. I didn’t have to blanch them at all. I halved or quartered them, depending on size, and got rid of any mushy ones from the bag. They were delicious!

  2. Brooke

    This really looks amazing. I too would probably be using frozen sprouts. I just wonder if they would be to watery?

  3. Stephanie

    This looks delicious!

  4. Bruce

    @Mollie, I have yet to make this but will be making it. I beg you, please do not use frozen brussel sprouts, fresh ones are just as easy to work with and taste so much better! Using the frozen ones and baking will just overcook them (if they already aren’t in their frozen state) blanching will allow them to get just tender enough to then bake with the pancetta shallots and cheese and absorb those flavors taking away a lot of the bitterness. Just my two sense.

    • Steven Short

      I totally agree that fresh is far superior than frozen since frozen are already pre blanched prior to packaging. As for bitterness I don’t think I would describe them as being so. Just my two cents. LOL

  5. Rebecca

    What do you think about making this GF? I have family members who are celiac but I think everyone would love this recipe! Maybe just an all-purpose GF flour blend? Or thickening up the sauce with cornstarch?

    • Elise

      Hi Rebecca, the sauce in this recipe is a mornay sauce (like bechamel but with added cheese). You create a roux using flour and fat and then add milk and cream to thicken into a sauce. I’m not familiar with how well GF flours do in methods like this. But it’s worth a Google search!

    • Mary Anna

      I low carb, and make my bechemal with heavy cream and cream cheese… probably 8 oz of cream cheese to about two or two and a half cups of cream. Just add the cream cheese to the butter & shallot mixture, let it soften, then add the cream and whisk. Then add the nutmeg, cheese, etc.

    • Amanda B

      I’ve successfully used rice flour in a 1:1 ratio to all purpose wheat flour in recipes like this. You wouldn’t need to change a thing, just use it exactly as you would APF. You could also try arrowroot or cornstarch, though I would do some research first because the method and amount may vary from grain flours.

  6. Sandy S

    My, this sounds good! The pictures are all very tempting and reading the recipe has my mouth watering! Certainly looking forward to making a GF version of this soon.

  7. Melanie

    This looks delicious and I was looking for a new side to add to the Thanksgiving table! Everything sounds perfect in the recipe except I can’t eat thyme, i have some weird allergy type reaction to it fresh or dried. I usually will substitute marjoram, oregano, basil and on occasion tarragon, depending on the recipe. I don’t think I have ever made anything with a creamy/cheesy sauce that calls for it so not sure what might substitute best, do you have an opinion? If not, I will probably go with marjoram as I have it on hand for the turkey and will report back my findings. Thanks so much for all the wonderful recipes you share!

    • Elise

      Marjoram should work fine as a replacement for thyme in this recipe. If you make it, please let us know how it works out for you!

  8. Kevin

    I think I’ll try this with the pancetta on the side (my wife is a pescotarian) and I’ll try sprinkling some course breadcrumbs on top.

    • Brian

      My wife also doesn’t eat meat. I substituted a little smoked salmon for the pancetta and it was delicious!

  9. Rachel

    @Rebecca, While I have not yet made this particular recipe GF (I am definitely planning on it for Thanksgiving), I have successfully made other recipes that call for making bechamel and mornay sauces with brown rice flour in place of wheat flour. It makes a nice sauce that tastes just the same as if you had used regular wheat flour.

  10. Rachel

    This looks great, and I don’t even like brussels sprouts!

  11. Tara

    They look amazing! Do you think these could be prepped ahead? Blanche the day before and refrigerate until your ready to throw the dish together?

    • Elise

      Could work. I haven’t done that yet, but it’s worth a try. You could also assemble the whole thing the day before and then cook it right before dinner. I haven’t tried that yet either, but I’ve had the leftovers of this batch for days, reheated, and they were great.

      • justine

        hello, what is the best way to reheat? microwave/oven? and what temp and for how long if i already cooked it the night before? I am planning on making this Wednesday night (as i have a lot to cook Thursday morning for Thanksgiving. also you said in the previous comment to assemble and then cook. How much of this dish would you assemble the night before? like up to which step. thank you so much Elise. love your recipes.

        • Elise

          Hi Justine, I would assemble the entire thing, chill it, and then cook it on Thursday. When I left the last comment I hadn’t tried doing that, but I later did, and am planning to do the same again this year. As for cooking the whole thing in advance and then reheating, probably 20 minutes at 350°F will do. Whatever it takes to heat it all the way through.

    • Steven Short

      I agree with Elise but the blanching takes only a few minutes off the cooking time. You might as well assemble the whole dish and either cook it before hand or with the rest of the meal. I would go with the latter myself. If you want to ensure that the sprouts hold their color texture, make sure you use very cold water or even ice water as I usually do. A few drops of vinegar of lemon juice doesn’t hurt either.

  12. m

    Elise, Any cheese substitute suggestions?

    • Elise

      Hmm, you could try making it without the cheese. You might want to add more pancetta to make up for the loss in flavor, and you’ll need to add more salt too.

      • Karen J

        “Without cheese” would really change the consistency, too!
        Good ideas for What to substitute? would depend on your reason *why*.

      • missy

        How about a different kind of cheese?

  13. Liz

    Nice recipe. Thank you.

  14. Steven Short

    M the term “Au Gratin” usually indicates a cheese sauce. If you asking if you could substitute Gruyere with another cheese, the answer would be yes. Swiss is similar but with a little more bite and doesn’t melt as well. Other suggestions would be Havarti or Muenster which have a milder flavor. I know from experience as my mother had a definite dislike of any form of Swiss cheese and would have to adjust recipes accordingly.

  15. m

    Thanks, Steven, very helpful! I think I will try the Muenster. Good suggestion!

    • Steven Short

      It would be my first choice as well.
      Bon appetite and wishing you and your’s a joyful holiday season.

  16. Jayne

    I recently made a broccoli gratin and loved it! Brussels sprouts will be so much better :-) I want to try this out very soon once I find some in my supermarket. This is nice and indulgent!

  17. Christy

    I think I might be in love… I’ve got to try this! I adore Brussels sprouts. :)

  18. Candy C.

    I love Brussels sprouts and this looks fabulous! :)

  19. anna @ annamayeveryday

    I like Brussels sprouts anyway but this gratin looks like the best way to serve them ever!

  20. Jessica @FoodLuvBites

    I’ve never seen Brussel Sprouts look this good and this amazing. I think I may sneak these into my sons dinner one evening. I personally haven’t been much of a fan with it but I will def give this one a try.

  21. Paul Wasmund

    Excellent Recipe that we tried last night. We substituted Colby Jack for cheese and bacon as that was what we had on hand. It’s a keeper and a wonderful side dish to the Prime Rib I cooked on my Big Green Egg. I love this site and use quite a few of your recipes. Thanks a lot.

  22. Emily @ Life on Food

    I made something similar this week. Best way I have ever eaten Brussels sprouts to date.

  23. Sylvia

    This Brussels Sprouts Gratin recipe sounds delicious. I love Brussels sprouts and usually just do them in the microwave with butter, salt & pepper. Will have to try something this recipe. I do think it would work with frozen, but would first thaw them and squeeze out as much water as I could. My mouth is watering and will have to head to the market.

  24. Elaine (BreatheEatLive)

    I just made a brussel sprouts stir fried last night for dinner, they’ve been a craving of mine lately! Your recipe sounds delicious! @Sylvia, if you sear the brussel sprouts in a pan with some olive oil for a few seconds, the water from the thawed sprouts will no longer be!

    • Karen J

      @Elaine ~ a touch of “sear” (browning) on the sprouts sounds like a wonderful addition to the depth of flavor! Yumm!

  25. Sara

    This was delicious! I doubled the recipe and added sliced turnips. This continues to be my go-to blog for outstanding recipes.

    • Steven Short

      I added Carrots, 1 in. sliced on the diagonal. Added color and a little sweetness plus increased vitamin A. Did not have much luck with frozen but fortunately my grocer usually always has fresh in stock.

  26. Judy Halfen

    The “sprouts” were on the dinner menu this evening. Excellent! What I liked about them too was that they were not “dead”….still had a little crunch. Leftovers for tomorrow night makes me a happy girl. Thank you for sharing this recipe.

  27. Ambar

    Love the multiple pictures explaining the recipe!

  28. Karen J

    This does sound (and look) delicious!
    My market currently has fresh whole stalks of sprouts for Thanksgiving – had an interesting conversation yesterday about “what to do with them?” Now I know!

    • Elise

      Hi Karen, I love buying the whole stalks and then snapping the sprouts off of the stalks. They’re so fresh that way! BTW, have you noticed how hard the stalk is? I thought I could easily chop it up and compost, but no. Even with a heavy cleaver it was difficult to chop up. It would make a good weapon though. Yikes!

      • Karen J

        I haven’t bought one yet, but we were discussing the possibility of peeling the stalk and cooking it like broccoli stems, too.
        Hmmm – the original Irish “shelayleigh”?

  29. Autumn

    Hi! Could I make this dish the night before Thanksgiving??

  30. Yasmine

    Can you give some suggestions on how to make ahead? Can I make the bachamel sauce, blanch the brussel sprouts today and assemble everything tomorrow? Thanks! it looks delicious.

    • Elise

      I’m assembling everything today and baking it tomorrow. We’ll see how that goes, I’m expecting it to work fine.

      Update: it worked like a charm!

  31. Bill

    Made this for Thanksgiving, widely appreciated! Thanks for the recipe!

    Assembled two dishes — baked one for T-day, and the other was refrigerated overnight and baked the next day to go with tri-tip. Both worked just fine.

  32. Gaelle

    Just finish this dish and started eating the parts that have cooled off. This is absolutely scrumptious.

  33. Jody

    This was a delicious side to a roast for Christmas dinner! Made ahead of time and baked as we enjoyed snacks before dinner. Everyone sopped it up and gave compliments! It was also great as a left over, broiled in oven on a lower broil. Turned the top crispy and my veggie-shy hubby asked for me to make it again.

  34. Maggie Unzueta @ Mama Maggie's Kitchen

    I wasn’t a big fan of brussel sprouts as a kid. I guess no one really is, are they? In a gratin, though… I could eat the entire thing!

  35. Roxanne

    This sounds great! Can it be made ahead and frozen ? Am trying to come up with recipes for Thanksgiving that I can do a week or two before so I’m not in the kitchen in the kitchen all day. Thanks in advance for any input.

    • Elise

      Hi Roxanne, that’s an excellent question! I have never tried freezing this. I have made put it together the day before and then cooked it on Thanksgiving day, but I haven’t frozen it. Perhaps someone else reading this could weigh in with advice?

    • eve

      I have a bunch of already blanched sprouts that we did not end up needing to cook on Thanksgiving (the first batch was plenty), so they the blanched ones have been in my fridge since Thursday. They still look good, so I am going to try this and freeze it. I will post an update when we take it out to eat it, whenever that is, probably Xmas.

  36. Samantha

    I need to double this recipe for Thanksgiving. What size pan should I use?

  37. Tom Combs

    My wife has been Celiac for several years so we always cook Gluten Free. We have found that GF all purpose flours work great for sauces/gravy’s. These flours are a mix of GF flours and work much better than a single GF flour. A good all purpose GF flour (my favorite GF flour is Domata) will work great in this recipe and I’m making it for Thanksgiving!

  38. Kristin C

    Was thinking about substituting frozen cut string beans? Do you think it would work?

  39. Barry

    I’ve used fresh out of the garden. It might be the soil, but Ive never gotten a bitter Brussel sprout from the garden. Kind of sweet.

  40. Jennifer

    All I could find were frozen brussel sprouts….any suggestions for making them work?

  41. lorena

    I made this for Thanksgiving dinner and end it up being too bitter. I followed the recipe, any idea what I did wrong?

  42. Paris

    What could be used in place of the pancetta? I don’t eat pork and wana make this because it sounds and looks delicious!