Brussels sprouts gratin with butternut squash is so delicious, even the pickiest of eaters will love it! Perfect for your holiday or Thanksgiving table.
Disclaimer: this post was sponsored by Mann’s. Thank you for supporting the brands that I love!
It’s getting to that time of year when we start to think about the holidays. We just had our Canadian Thanksgiving and it got me thinking about the lack of holiday recipes on my site. Well that’s going to change, and we’re starting with this delicious Brussels sprouts gratin with butternut squash.
I’ve partnered with Mann’s on this post and am featuring their convenient Family Favorites line, which are trimmed, washed and ready for you to use straight out of the bag! Mann’s Brussels Sprouts and Butternut Squash made this gratin recipe so incredibly simple to get on the table.
Look for Mann’s Family Favorites products in the produce section of your grocery store, or check the product locator on their site!
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We love this brussels sprouts gratin because
- it’s ready in under an hour
- the flavor is so good, it will convert even the pickiest eater into a brussels sprouts fan
- you can get your veggies into the oven in under 10 minutes so you can focus on the sauce
How to make brussels sprouts au gratin
Compared to my usual 10-minute side dish recipes (like these Snap Peas 3 Ways and these Broccolini 3 Ways), these brussels sprouts au gratin are a tiny bit more effort. I consider these a special occasion recipe, like Sunday dinner, Thanksgiving, or Christmas, though you could totally get these on the table for a weeknight (they really only take 50 minutes total time).
There are three super simple components to this brussels sprouts au gratin recipe:
- veggies: Mann’s brussels sprouts and butternut squash, which we roast up for 35 minutes. Get this in the oven and we can focus on the cheese sauce.
- cheese sauce: made with a little butter, flour, sage, nutmeg, milk and cheese. Easy to make, but make sure to add the milk gradually. Watch the video in the recipe card for a visual explanation!
- cheese: for sprinkling on top and getting that cheesy crust. Enough said.
After roasting the brussels sprouts and butternut squash, we toss it in the cheese sauce and sprinkle with cheese; return the brussels sprouts au gratin to the oven for 10-15 minutes.
Can I swap out the brussels sprouts or the butternut squash in this gratin? Yes! You could swap for any number of veggies including broccoli, cauliflower, and maybe even sweet potatoes (PS- Mann’s has these veggies in their Family Favorites line as well!). You may need to adjust the roasting time depending on the veggie.
Can I swap the flour for almond flour or a low carb flour in this brussels & butternut squash gratin? I have not tried. I have read that almond flour doesn’t thicken the same way as all purpose flour. I’d try this cheese sauce recipe instead!
Can I swap the all purpose flour for a gluten-free alternativebrussels & butternut squash gratin? I’ve seen several recipes that use cornstarch instead of flour; I’d try swapping with an equal amount of cornstarch (though I haven’t tried).
Can this brussels & butternut squash gratin be made ahead and reheated? Yes! It is best served fresh, but you can bake ahead. Cover and reheat at 350°F until warmed through (I’d guess 20 or so minutes).
What to serve with brussels sprouts and butternut squash gratin
This recipe is really great as part of a holiday feast, and would go great with turkey (stay tuned for my favorite dry-brined turkey recipe coming soon!). Here are some other ideas for serving this butternut squash gratin:
- Perfect Baked Chicken Breast
- One of these 7 Instant Pot Chicken Breast Recipes
- this Baked Lemon Pepper Chicken
- this Autumn Apple Farro Salad or my favorite Staple Kale Salad
- this Herb Crusted Broiled Salmon
Tips for this brussels sprouts gratin with butternut squash
- use a 9×13 inch baking dish (I use this one from Crate & Barrel)
- use one of these re-usable silicone lids to cover and reheat in the oven
- looking for more brussels sprouts recipes? Try this Apple Fennel & Brussels Sprouts Slaw, this Slow Cooker Brussels Sprouts with Cranberries, Pecans & Butternut or this Cranberry Balsamic Sheet Pan
Brussels Sprouts Gratin with Butternut Squash
- 24 oz brussels sprouts (two 12 oz bags from Mann's Family Favorites Line)
- 20 oz butternut squash, peeled & chopped into 1 inch cubes (1 20 oz bag from Mann's Family Favorites line)
- 2 tablespoons olive oil
- 1 1/2 tablespoon unsalted butter (21 g)
- 1 teaspoon dried sage leaves (crumbled)
- 1/8 teaspoon nutmeg
- 3/4 teaspoon salt
- 1 1/2 tablespoons all purpose flour (23 g)
- 1 cup 2% milk
- 1 1/4 cups shredded cheese (divided; mozzarella works but go for gruyere if you can!)
- Heat oven to 425°F.
- Trim ends off brussels sprouts and slice them in half. Toss with the butternut squash in olive oil, salt & pepper.
- Arrange in a 9 X 13 inch baking dish and roast for 25-35 minutes, until they are soft.
- While vegetables are roasting, make the cheese sauce: in a medium pan, melt the butter over medium heat. Whisk in the sage, nutmeg, salt and flour.
- Add the milk gradually over the course of several minutes, whisking so that the flour doesn't clump. Cook until slightly thickened, then stir in 3/4 cup of the shredded cheese. Remove from heat when cheese has melted in and sauce is thickened.
- Once vegetables are tender, pour the sauce over top. Toss veggies in sauce, then sprinkle remaining cheese over top.
- Return to the oven for another 10-15 minutes, until sauce is bubbling and cheese is melted.
Storage & reheating
- Store in a covered container in the fridge. Heat in the microwave until steaming hot OR bake in a covered container in the oven at 350°F for about 20 minutes or until warmed through.