My butternut squash casserole is warming and cozy, filled with fall colors and lots of earthy flavors. Prepared with cubed and roasted butternut squash and apples that are layered with sweet sausage, caramelized fennel and onions, plus a sprinkle of melted Gruyere cheese, this festive dish is the epitome of autumn!
Brimming with the Flavors of Fall
I find it a total joy and wonderful culinary challenge to come up with new, seasonal recipes each year that make use of the ingredients that happen to be bountiful at any given time.
Since fall is my favorite season, I love to create cozy, comforting and nourishing recipes centered around various types of squash. Squash is so incredibly versatile and quite easy to cook with, not to mention healthy and gloriously colorful!
Butternut squash is a very popular variety of squash and one of my personal favorites, as I use it in many of my seasonal soups or as a component in a hot, savory dip. We even like to enjoy it roasted up and mashed until smooth, served as a vibrant alternative to mashed potatoes.
This year, I was craving something a little different, a recipe that went more in the direction of a casserole, so I created my butternut squash casserole recipe brimming with loads of fall flavor.
I layered it with lots of sweet-savory and earthy ingredients such as apples roasted alongside of the butternut squash, plus caramelized sweet sausage, fennel and onions, and a sprinkle of Gruyere cheese, making it a terrific option to serve as a casual weeknight meal, or as an offering fit for the holiday table.
Perfectly warming, comforting and delicious, this butternut squash casserole is a terrific, gluten-free alternative to a traditional bread-based stuffing recipe for the holiday table, or simply a fantastic, seasonal “everyday” type of recipe to prepare if you're looking for a delicious new way to transform butternut squash!
A Butternut Squash Casserole Recipe Layered with Seasonal Ingredients
Because I love both sweet and savory elements in this butternut squash casserole, I combine medium size cubes of butternut squash with cubes of fresh apples plus a touch of pure maple syrup, and then roast those together just until tender.
I also love the flavor of fennel, and caramelize a couple of thinly sliced bulbs in a pan along with a thinly sliced onion, until golden-brown, slightly sweet and jammy.
Sweet Italian sausage is a tasty twist in this casserole, and I appreciate the addition of a little protein, but it can easily be left out of the dish in order to keep this casserole completely vegetarian, if desired.
I gently combine all the ingredients in a baking dish and then finish with a light sprinkle of Gruyere cheese for a bit of savoriness before baking to hot, delicious perfection!
Here's a sneak peek at my butternut squash casserole recipe:. (or just jump to the recipe...)
- To begin, I toss cubed butternut squash with cubed apples, maple syrup and some seasonings, and roast until tender and golden.
- While the squash and apples roast, I caramelize some sweet Italian sausage in a skillet, then remove that and add into that same pan some thinly sliced fennel and onions, and saute those together until caramelized.
- To assemble the butternut squash casserole, I combine the caramelized sweet Italian sausage, fennel and onions with the roasted butternut squash and apples, spoon into a casserole dish, and sprinkle over some Gruyere cheese
- Then, I broil the casserole for a few minutes until the cheese is melted and golden-brown on top, sprinkle over some fresh or fried sage leaves and serve.
Recipe
Butternut Squash Casserole
by Ingrid Beer

Category: Side
Cuisine: American
Yield: Serves 6
Nutrition Info: 288 calories per serving
Prep Time: 20 minutes
Cook time: 45 minutes
Total time: 1 hour, 5 minutes
Ingredients:
- 2 pounds butternut squash, peeled and cubed into medium-size chunks
- 2 Honeycrisp apples, peeled, cored and cubed into larger chunks (to match the squash)
- Olive oil
- Salt
- Black pepper
- 2 tablespoons pure maples syrup, divided use
- ½ teaspoon ground, dried sage
- 1 ½ teaspoons Herbes de Provence
- ½ pound sweet Italian sausage, casings removed and crumbled
- 2 small fennel bulbs (stalks/fronds removed), cut in half lengthwise, cored, and thinly sliced
- 1 onion, quartered and thinly sliced
- 1 cup grated Gruyere cheese
- Fresh sage leaves (fresh or fried), for garnish
- Preheat your oven to 425°, and line a baking sheet with foil lightly misted with cooking spray.
- Place you cubed butternut squash and apples into a large bowl, and drizzle in about 2 tablespoons of oil. Sprinkle over a generous couple of pinches of salt and black pepper, along with 1 tablespoon of the maple syrup, the dried sage and the Herbes de Provence; toss to coat.
- Turn the mixture out onto your prepared baking sheet, and roast for about 35 minutes, stirring occasionally for even roasting, or until the squash is tender.
- While the butternut squash and apples roast, place a large skillet (cast-iron is great) over medium-high heat, and add a small drizzle of olive oil; once the pan is very hot, add the crumbled sweet Italian sausage in and cook until browned and cooked through, a few minutes. Remove from the pan and keep in a bowl.
- If additional oil is needed in the pan/skillet, add a small amount in; then, add the sliced fennel and onion into the pan and caramelize together for about 10-12 minutes, or until deeply golden and a bit jammy in texture. Remove from pan and add to the sausage.
- Once the butternut squash and apples are tender and roasted, switch your oven setting to “broil”.
- To prepare the casserole, carefully spoon the roasted butternut squash/apples into a large bowl, and add the sausage/fennel/onion mixture to that. Pour in the remaining 1 tablespoon maple syrup and toss to combine (add a touch more salt and pepper to create a sweet-savory flavor), then spoon into a medium size (roughly 9 by 13) baking dish.
- If preparing fried sage leaves as a garnish, heat about ¼ cup of oil in a small sauce pan or pot, and once shimmering, add the sage leaves and fry for about 20 seconds, then remove them and drain on paper towels. Sprinkle lightly with salt and set aside.
- To finish the casserole, top with the grated Gruyere cheese and place into the oven under the broiler for a few minutes, until the cheese is melted and golden-brown.
- Garnish the butternut squash casserole with either the fried sage leaves or fresh ones, and serve.
Tips & Tidbits for my Butternut Squash Casserole:
- Pre-cut butternut squash, for convenience: Any time I can find some pre-packaged/pre-cut butternut squash, I opt for that. I appreciate not having to monkey around with peeling and seeding the whole squash. But if you have a whole squash on hand, feel free to use it, cutting it into medium-size chunks for the recipe.
- Sweet apples to use in this casserole: Honeycrisp apples are my favorites to eat and cook with, as they are both sweet and tart, not too hard nor too soft. Other varietals that are good are Golden Delicious, Gala, or Jonagold.
- Vegetarian butternut squash casserole: If you'd like to keep this casserole completely vegetarian, then simply omit the sweet Italian sausage, and proceed with caramelizing the fennel and onions. You could even use a vegan cheese in place of the Gruyere if you'd like to go completely vegan with this recipe, or just combine the ingredients and leave the cheese off altogether.
- Other cheeses to top the casserole with: Some other cheeses that would work well as a topper with this casserole are mozzarella, white cheddar, or Jack cheese. You could even crumble chunks of brie over top if you're looking for extra creamy decadence.
Craving more delicious recipes like this one? Check out this Butternut Squash Soup, this Roasted Butternut Squash Mash, this Butternut Squash Lasagna, or this Hot Butternut Squash and Spinach Dip!
Caroline
Ahhh, there’s a reason I picked up some nice butternut squash while wondering what I’ll do with it! Have already a yummy recipe but this looks to be the next keeper for sure! Can’t wait to try this! Thankyou Ingrid!
The Cozy Apron
Hi Caroline, perfect! So many of us have some variety of squash (often butternut) hanging out in our fridge or pantry, so I was hoping many would benefit from this particular recipe.
I hope you and your loved ones enjoy it—happy cooking to you, Caroline! 🙂
Candace
This was amazing, Ingrid! A perfect recipe for us at The Squash House! (And no, in case you wondered, that isn't really our last name, it's what we named our home after retiring as an ode to one of our favorite novels, Winter's Tale by Mark Halprin). The sweetness of the squash combined with the herbs and fennel were just the perfect combination! Can't wait to see what you serve up next!
Cheers!
The Cozy Apron
So glad to read that, Candace! My heart is so full that you're enjoying the recipes so much.
And by the way, I really appreciate what you shared about the "Squash House" name. I was, indeed, wondering how that came about! I assumed it was something personal to you and your family, and to learn that it's an ode to a favorite novel is beyond whimsical and lovely. (It's actually something that my husband and I would do.)
Thank you so much for giving me a little "peek" into your "world"! 🙂
Gina
First time making a recipe from this site. The photo popped up on Pinterest and it looked good and seemed like interesting ingredients so I gave it a try.
Yum! A delicious combination of textures as well as sweet, salty, and herby flavors. I had only one fennel bulb but it was plenty for me, and I also did not have fresh sage leaves for garnish. Other than that, followed the recipe exactly.
Ate it as a side then the leftovers as a main dish for lunch. Will definitely make this again.
The Cozy Apron
Gina, fantastic! So happy to read that you enjoyed the combination of fall flavors, a little bit sweet and savory.
Happy cooking!
Marianna
Excellent recipe, thank you! I had to sub sweet potatoes for butternut since it's apparently out of season and used a locally made bratwurst for the sausage. Lovely, lovely dinner!
The Cozy Apron
Marianna, thanks for sharing your experience!
I truly do hope you get the chance to prepare this recipe with the butternut squash once it's back in season, as I think you'll really enjoy it. But the sweet potatoes were a fantastic substitution! So glad you enjoyed.
Linda
I was wondering if you think this could be made ahead of time (except for melting the cheese) and then reheated later in the day? - wasn't sure what temp to reheat or for how long?
The Cozy Apron
Hi Linda, you certainly can. It's good that you will leave the cheese off, and add that when you're ready to reheat and enjoy.
I would recommend that if you are prepping ahead and refrigerating it, then allow it to come to room temp before baking. This will help it to not be ice cold, and make the reheat time shorter.
If you're simply prepping it earlier the same day, you could probably get away with just leaving it at room temp, then adding the cheese on top and reheating at 350° for 15 -20 minutes, or until the cheese melts and the casserole is warmed through.
I hope this helps, and I hope you enjoy!
Cherie
I loved this recipe. I could have eaten the whole thing as I finished making it!! I wanted to take it to my son’s house the next day. I left the cheese off of it and refrigerated the casserole. The next day, I set it out for thirty minutes and then put the cheese on top, and baked it for 15-20 minutes. I should have cooked it for 30-40 minutes. It was not as hot as I like my food but very delicious:)
The Cozy Apron
Hi Cherie, thank you very much for sharing your experience! Very glad you enjoy the recipe, and well done on the prep for the following day.
I'm a stickler for very hot food as well, so I'm sorry that the casserole wasn't quite hot enough the day you baked it off; but it seems you have a strategy for a longer cook time next time, so I hope it'll be just perfect for you then. 🙂
Happy cooking, Cherie!
Maryann
Thanks for this recipe-I did a trial run and we loved it. I'm making it for Thanksgiving. In the trial run I used apple smoked instead of sweet sauce and it was goof, bur I bought sweet sausage for the Thanksgiving dinner. Thanks for the make-ahead tips!
The Cozy Apron
That's terrific, Maryann! Happy to read you all loved it, and I hope it brings you and your loved ones comfort and coziness for the holiday gathering!
Katie
Thank you so much for sharing this!! I just made this now for tonight’s dinner (it’s 2:15 here) and I don’t think there will be any left!
I really enjoyed it pre cheese (I was picking at it!) and for a more savory taste, with the cheese.
A really good recipe for fall that I’ll be sure to make again!
The Cozy Apron
Hi Katie, that's fantastic! (Hope the casserole lasted to dinner time, btw... 🙂 )
May you enjoy this all season long. Happy cooking!
Tiffany
Made this tonight! My first time cooking with Fennel so I was a little nervous as I tend to not like the flavor of anise . I scaled it back to play it safe. Turned out delicious! Maybe next time I’ll use the full amount 🙂 pretty quick and easy dish to make. Will def make this again!
The Cozy Apron
Hi Tiffany, thanks for sharing your experience! I'm really glad to read that you enjoyed the recipe, even with the fennel, haha. 😉
Happy cooking!
Hayley
This was absolutely amazing! I found this recipe when looking for a butternut squash casserole to try and this one sounded incredible... I was right! Thanks so much for the beautiful recipe!
The Cozy Apron
Aw, Hayley, thanks so much for that! So glad to read you enjoyed this casserole so much. 🙂
Kim
Adding to my Thanksgiving menu. Any substitutions for fennel? We aren’t big fans of the flavor. Thank you.
The Cozy Apron
Hi Kim, that's terrific!
So, I'd say that you could add additional onion, plus a touch more butternut squash and apple, in place of the fennel. (Funny enough, the fennel, once caramelized, takes on a much more mild, sweet flavor, not as anise-y as when fresh, FYI. 😉 )
The sliced fennel is roughly 1 3/4 to 2 cups worth, so just sub other ingredients to make that up. Hope that helps, Kim! Happy holidays!
Brooke Richardson
Hi, can you use frozen butternut squash? Thanks so much!
The Cozy Apron
Hi Brooke, I would not recommend using frozen squash for this casserole, as will not yield the same result as fresh cubes of butternut once roasted.
Miya9693
Hello
I've discovered your site by chance, looking for new sqush recipes (can't get enough !) and I am delighted with it ! Not always easy to find all the requiered ingredients in Belgium but I figured out a way to replace the ones that are missing.
Anyway, this dish is tasty and perfect for these cold winter evenings.
Thanks !
Ingrid Beer
Thanks so much for sharing your experience with the recipe—thrilled you enjoyed it so much! It truly is comforting during the colder months, and a nice healthy option when you're craving a dish with squash as its star.
Happy cooking to you!
Carol
This recipe was absolutely delicious! Tried it last night and can't wait for leftovers tonight. Great flavors. Perfect meal for Fall !
The Cozy Apron
Carol, that's fantastic! So happy to read that you had success with this comforting and earthy fall recipe. Enjoy your leftovers! 😉
Molly McDonald
Hi! What would you recommend as a main dish to serve with this?
The Cozy Apron
Hi Molly, funny enough, this casserole is sort of a main dish. Because it has the sausage in it, and is so hearty, it doesn't need much else except perhaps a salad on the side. But I've had folks tell me that they served it as part of their Thanksgiving spread, so you could always serve some roasted turkey breast or roasted chicken breasts (search my site for those, if interested) as an accompaniment.
Amy
Thinking about making this as a Thanksgiving side this year - it looks amazing! I would need to pre- make and freeze, re-heat. Does this recipe work well for make-ahead?
The Cozy Apron
Hi Amy, how fantastic you're thinking about prepping this for Turkey Day!
So, here's what I'd say: you can totally prep this dish ahead, but I would not recommend freezing it.
You can make it several days ahead, and wrap it tightly in plastic wrap and store in fridge, then bring to room temp for an hour or two, top with the cheese, and bake until hot, about 25 minutes. But the difficulty with freezing anything containing butternut (or any other) squash is that the squash has a lot of water in it, and once frozen, can become mushy or mealy—a strange texture—after cooking.
So if you're wanting to prep ahead, just roast the squash and apples according to recipe instructions, cook the other ingredients according to recipe instructions, and allow everything to completely cool before combining and adding to a baking dish (you don't want things steaming). Wrap in plastic and keep in fridge until ready to top with cheese and bake until hot.
Hope that helps!
Mary
I'm definitely going to try this. I do have a dilemma though. I just made a chicken and butternut squash crockpot dish. I had made this before and it was wonderful. This time I used frozen, cubed butternut squash. The squash ended up being mush and almost burnt looking. It was horrible. Thankfully the chicken was good! It was supposed to be slow cooked for 7 hours and the recipe said not to lift the lid, so I didn't look at it until almost 6 hours. Do you know what caused this?
The Cozy Apron
Hi Mary, because the crock pot recipe you are describing is not one of mine, I can only guess since I don't have the info. But it sounds like the frozen butternut squash is the culprit, along with the long cook time. Not a good combo. 🙁
I would not recommend using frozen squash because it contains a lot of water, so when it freezes and then thaws, it becomes, well, "mush". (Actually, you could get away with using frozen if making a butternut squash soup, for instance, that you will puree until smooth, but other than that, I'd avoid it.)
Squash of any kind (but especially butternut) is just one of those ingredients that is best fresh. You can purchase the pre-peeled and pre-cubed butternut at most markets these days to save on time, so I'd recommend going with that.
Having said all of that, I think you'll love this recipe, should you try it. Just make sure to use fresh butternut squash and not the frozen for optimal texture and presentation. 😉 Happy cooking!
Cathy
I’m not familiar with cooking with fennel. Can you give an estimate in cups as to how much I should be using? Thanks!
The Cozy Apron
Hi Cathy, I'm thinking this would be (roughly) 1 3/4 to 2 cups of sliced fennel. Hope that helps!