Introduction

This Cheesy Butternut Squash Casserole combines roasted squash and apples with savory sausage and caramelized fennel for a comforting dish full of flavor. Topped with melted Gruyere cheese and an optional crispy sage garnish, it’s perfect for cozy dinners or holiday gatherings.

A single square piece of casserole sits on a white plate with a shiny silver fork beside it. The dish has three visible layers: the bottom layer is a soft yellow-orange base made of cooked squash or sweet potatoes; the middle layer is made of browned ground meat, light to dark brown with a crumbly texture; the top layer is melted cheese, golden and bubbly with some browned spots. The edges of the cheese drip down slightly over the meat and yellow layer, and the texture looks gooey and rich. Photo taken with an iphone --ar 4:5 --v 7

Ingredients

2 lb butternut squash, peeled and cut into medium cubes
2 Honeycrisp apples, peeled, cored, and diced to match squash size
2 tbsp olive oil (divided as needed)
Generous salt, to taste
Black pepper, to taste
1 tbsp pure maple syrup
1/2 tsp dried ground sage
1 1/2 tsp herbes de Provence
1/2 lb sweet Italian sausage, casings off and broken up
2 small fennel bulbs, halved, cored and thinly sliced
1 onion, cut into quarters and thin strips
Additional olive oil, as needed
1 tbsp maple syrup (for assembling)
1 cup Gruyere cheese, shredded
Fresh sage leaves (for garnish—use fresh or fried)
1/4 cup oil (for frying sage, optional)
Extra salt and pepper, as desired

Instructions

Step 1: Preheat your oven to 425°F and line a baking sheet with foil, lightly misting it with cooking spray. In a large bowl, combine the cubed butternut squash and diced apples. Drizzle with 2 tablespoons olive oil, then sprinkle generously with salt and black pepper. Add 1 tablespoon maple syrup, dried sage, and herbes de Provence. Toss to coat evenly, then spread on the baking sheet. Roast for about 35 minutes, stirring occasionally, until the squash is tender.
Step 2: While the squash roasts, heat a large skillet over medium-high heat with a small drizzle of olive oil. Add the crumbled sausage and cook until browned and cooked through, stirring occasionally. Remove the sausage and set aside in a bowl.
Step 3: If the skillet is dry, add more olive oil. Add the sliced fennel and onion to the pan and cook over medium heat for 10–12 minutes, stirring occasionally, until caramelized and golden. Remove from the pan and add to the bowl with the sausage. Let the pan cook on low for an extra minute to deepen the sweetness.
Step 4: Switch your oven setting to broil. In a large bowl, combine the roasted squash and apples with the sausage, fennel, and onion mixture. Pour in the remaining 1 tablespoon maple syrup and toss to blend flavors. Season with salt and pepper to taste. Transfer the mixture to a 9 by 13-inch baking dish.
Step 5: (Optional) For crispy sage garnish, heat 1/4 cup oil in a small saucepan over medium-high heat. Once shimmering, fry the sage leaves for about 20 seconds until crisp. Remove immediately to paper towels to drain and sprinkle lightly with salt. Set aside.
Step 6: Top the casserole with shredded Gruyere cheese. Place under the broiler for a few minutes until the cheese is melted and golden brown. Watch closely to prevent burning.
Step 7: Remove the casserole from the oven and let it cool slightly. Garnish with fried or fresh sage leaves. Serve warm and enjoy the sweet, savory, and herbal flavors.

Tips & Variations

Use a mix of Gruyere and Swiss cheese for a different but equally delicious flavor.
Substitute sweet Italian sausage with turkey sausage for a lighter option.
Try adding chopped walnuts to the topping for extra crunch.
If you prefer less sweetness, reduce the maple syrup by half.
Fennel can be replaced with leeks or shallots if unavailable.

Storage

Store leftover casserole in an airtight container in the refrigerator for up to 3 days. Reheat gently in the oven at 350°F until warmed through to retain the crispy cheese topping. This dish can also be frozen for up to 1 month; thaw overnight in the fridge before reheating.

How to Serve

A white rectangular dish filled with a baked mixture showing three main layers: soft orange butternut squash cubes, browned cooked ground sausage pieces, and a creamy melted cheese layer that blankets the ingredients, slightly browned on top. Scattered on the surface are fresh green sage leaves. A silver spoon is lifting a portion, revealing the mix of orange squash and brown sausage with the creamy cheese stringing between. The dish sits on a white marbled texture. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I make this casserole ahead of time?

Yes, you can assemble the casserole up to a day ahead and keep it covered in the refrigerator. Add the cheese topping and broil just before serving for best results.

What can I use instead of butternut squash?

You can substitute other winter squash varieties like acorn or delicata squash, but roasting times may vary slightly depending on the squash’s density.