This Butternut Squash Pasta Bake is a hearty casserole layered with roasted squash, caramelized onions, creamy cheese sauce, and hot Italian sausage. It's the perfect comfort food for cooler evenings, balancing rich flavors with a touch of sweetness from the squash.

Growing up in northern New York, pasta casseroles were a staple at family gatherings, often baked until bubbly and golden. This recipe reminds me of those cozy Sunday dinners, but with the seasonal twist of roasted squash that adds a beautiful autumn flavor. If you've enjoyed my Butternut Squash Galette, you'll love this pasta bake too.
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Why You'll Love This Recipe
Family favorite: perfect for feeding a crowd or serving as a holiday side.
Rich flavor: creamy cheese sauce paired with savory sausage and caramelized onions.
Seasonal comfort food: Roasted butternut squash and sage bring an autumn warmth, while the bubbling pasta casserole is satisfying and filling.
Key Ingredients for Butternut Squash Pasta Bake
See the recipe card below for a fill list of ingredients and instructions.
- Butternut squash: roasted until tender for natural sweetness.
- Hot Italian sausage: adds hearty protein and bold flavor
- Fresh sage and thyme: infuse the dish with earthy, aromatic notes.
- Caramelized onions: bring depth and sweetness to balance the savory elements.
- Colby cheese: melts into a creamy sauce that coats the pasta perfectly.
- Spinach: fresh greens that wilt beautifully into the casserole.
Ingredient Substitutions
- Pasta: use penne, rigatoni, or fusilli if you don't have cavatappi.
- Cheese: swap Colby with sharp cheddar or Gruyere for different flavors.
- Sausage: try mild Italian sausage, or ground turkey sausage for a lighter option.
Variations on Butternut Squash Pasta Bake
- Vegetarian version: leave out the sausage for a meatless bake.
- Crunchy topping: use crushed Ritz crackers or panko instead of seasoned breadcrumbs.
- Extra creamy: stir in ricotta cheese or mascarpone before baking.
Tips for the Best Pasta Bake
- Roast squash fully: make sure it's fork-tender for the best texture.
- Caramelize slowly: take time with the onions to deepen flavor.
- Mix well: stir sauce, pasta, sausage, and greens thoroughly so every bite is creamy and cheesy.
How to Store and Reheat
Refrigerate leftovers in an airtight container for up to 4 days. Reheat in the oven at 350°F, covered with foil, until warmed through. Individual portions an be microwaved, but the oven keeps the topping crisp.
Serve With...
This butternut squash pasta bake makes a comforting main dish. Pair it with a Quick Dinner Rolls for a soft, buttery side, or serve alongside a fresh Shrimp Caesar Salad. For dessert, finish the meal with a slice of Banana Marble Bundt Cake
More Easy Pasta Recipes You'll Love
If you enjoy this Butternut Squash Pasta Bake, try my Cheese Ravioli with Butternut Squash and Sage Browned Butter, Chicken Parmesan Casserole, Crab Macaroni and Cheese, and Creamy Pesto Pasta.
When you make this recipe, please comment below and let me know what you think. I'd love it if you tag me on Instagram @grumpyshoneybunch or #grumpyshoneybunch so I can see your photos!
If you love this recipe, please leave a ⭐⭐⭐⭐⭐ rating
📖 Recipe

Butternut Squash Pasta Bake with Sausage
Equipment
- Large casserole dish
- Roasting pan
- Saucepan
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Ingredients
- 3 cups butternut squash cubed and peeled
- 1 tablespoon olive oil divided
- 1 tablespoon fresh sage chopped
- 4 cloves garlic
- ½ teaspoon salt
- ¼ teaspoon fresh ground black pepper
- cooking spray
- 1 medium onion vertically sliced
- 4 cups fresh spinach
- 2½ cups low fat milk
- 2 thyme sprigs
- 2½ tablespoons flour
- ½ cup low fat milk
- 8 ounces colby cheese shredded
- ¼ teaspoon grated whole nutmeg
- 1 pound cavatapi pasta cooked according to directions (I used cavatapi)
- 1 pound hot italian sausage crumbled and cooked
Instructions
- Preheat oven to 350.Combine squash, ½ tablespoon oil, sage, garlic, ½ teaspoon salt, and black pepper in a large bowl; toss to coat. Arrange squash mixture on a baking sheet coated with cooking spray. Bake at 425° for 30 minutes or until squash is tender. While squash is roasting, cook pasta according to package directions. Drain and return to stock pot.
- Heat remaining oil in a large Dutch oven over medium-high heat. Add onion, and sauté for 4 minutes. Reduce heat to medium-low; continue cooking for 20 minutes or until golden brown, stirring frequently. Place onion in a bowl.
- Heat 2 ½ cups milk, and thyme in a medium saucepan over medium-high heat. Bring to a boil; remove from heat. Let stand for 10 minutes. Discard thyme. Return pan to medium heat. Combine remaining ½ cup milk and flour in a small bowl. Add to pan, stirring with a whisk until blended. Bring to a boil; reduce heat, and simmer for 5 minutes or until thickened, stirring constantly. Remove from heat; stir in teaspoon salt, cheese, and nutmeg.
- Add spinach and hot sausage to cooked pasta. Pour cheese sauce over top of pasta mixture and stir to coat.
- Place pasta in a large casserole and sprinkle with Italian Seasoned Breadcrumbs. Bake for 30-40 minutes or until hot and bubbly.






OakMonster says
Hanna and I are DYING here. We shouldn't have looked at this first thing in the morning. LOL
MY grumpy is out of town too. Perhaps I should make this for dinner tonight. Yep. Definitely will make this for dinner tonight!
Sarah Olson says
I love this take on mac and cheese! I love that you added some veggies. 🙂
Mary Ellen says
This looks amazing. I have yet to add squash to my mac and cheese. I have to try it now that you've added some caramelized onions and sausage.
Patsy K says
Total comfort food! I've got to try this!
Catherine says
Oh my!! What a delicious mac-n-cheese!!! This meal would make anyone happy!!! Blessings, Catherine
Marye says
Just yes. Now.
Mandee Pogue says
Oh wow! This looks really goood! I have some BNS puree in my freezer that I could make a variation of this with! Thanks for the yummy and creative recipe!