Spaghetti Squash filled with Creamy Pumpkin Sauce, Gruyere cheese, and rosemary-fried walnuts. This pumpkin pasta sauce is vegetarian, low carb, and sure to be a fall favorite!
The challenge, however, is creating more nutritious, plant-forward takes on cozy classics without scarifying flavor. Which is where this hearty spaghetti squash recipe comes in.
If you're new to roasting spaghetti squash, here are a few reasons to love it:
- Spaghetti squash is 100% allergen friendly--free of gluten, dairy, soy, and nuts--and easy for kids to eat.
- It's a great way to sneak in a few extra servings of veggies (especially for the picky eaters!)
In this recipe, spaghetti squash is filled with a creamy pumpkin tomato-sauce made with real pumpkin puree. It's blanketed in gooey cheese and finished with rosemary walnuts.
It's the perfect alchemy of creamy and crunchy, as well as hearty and healthy.
How to Make Pumpkin Pasta Sauce:
Similar to vodka sauce (minus the vodka), this pumpkin pasta sauce is delightfully creamy with bright notes of tomato.
Pumpkin is the key ingredient that gives the pasta sauce its creamy consistency. The sauce’s pumpkin flavor, however, is pretty subtle, so if you desire a stronger “pumpkin” taste, feel free to up the spices.
- Spaghetti Squash: Baked spaghetti squash creates luscious strands of spaghetti-like "noodles" that are naturally low carb and nutrient rich. They're a fantastic substitute for classic pasta if you're trying to lighten up or reduce the carb load of a dish.
- Pumpkin Puree: Make sure you're using 100% pumpkin puree rather than pumpkin pie filling. Pumpkin is a great source of Vitamins A and C.
- Tomato Paste: Tomato paste lends rich notes of umami to the sauce. The key is to COOK the tomato paste for 2 to 3 minutes to really unlock its flavor potential.
- Spices: Freshly grated nutmeg and oregano add cozy fall flavor to the sauce.
- Heavy Cream: A little goes a long way! Alternatively, you can use canned coconut milk.
- Cheese: A combination of shredded mozzarella and Gruyere cheese give this dish all of its cheesy goodness. Mozzarella is super meltable, while Gruyere adds nutty flavor.
- Rosemary: I love the combination of rosemary and walnuts for the topping. Alternatively, you can use sage or fresh thyme.
- Walnuts: A rich source of heart-healthy fats that adds textural intrigue to the dish.
Step 1: Roast the Spaghetti Squash
Start by preheating your oven to 400°F. Next, use a large, sharp chef's knife to carefully slice the spaghetti squash in half lengthwise. Lightly coat the flesh with cooking spray or olive oil, and season with salt and pepper.
Place the squash halves face-down on a baking sheet. Roast for 30 to 40 minutes, or until fork-tender.
Step 2: Prepare Rosemary Walnuts
Meanwhile, heat 1 Tbsp. olive oil in a large skillet over medium. Add walnuts and rosemary; gently saute for 5 minutes, or until aromatic. Season with a pinch of salt and transfer to a bowl.
Step 3: Make Pumpkin Pasta Sauce
Add remaining 2 Tbsp. oil to the hot pan. Add shallots and garlic; cook 3 minutes. Add tomato paste and cook until it turns a deep crimson red, about 3 minutes.
Add pumpkin puree, water, heavy cream, oregano, nutmeg, chili flakes, and salt; gently simmer for 8 to 10 minutes, until the sauce reduces.
Step 4: Fill Squash Boats
Remove squash from the oven and turn over to reveal flesh. Divide the pumpkin pasta sauce evenly into the cavities of each squash boat. Sprinkle cheese overtop and bake until bubbly. Finish with rosemary walnuts!
Expert Tips for Roasting Spaghetti Squash
- Cut your squash in half lengthwise. A SHARP chef’s knife and some elbow grease are key!
- Use a large spoon to scoop out the seeds and stringy insides. You can either discard the seeds or roast them like you would pumpkin seeds! They make a great crunchy snack.
- Roast the squash halves cut side-down on a baking sheet coated with foil for easy clean up. When the flesh makes contact with the pan, it will caramelize as it bakes.
- A good rule of thumb for doneness is if the spaghetti-like strands easily release from the skin. If not, continue baking and check on it every 5 to 10 minutes.
Here are some of my favorite recipes and sides to serve with this spaghetti squash:
- Salad: You can’t beat this 10-Minute Warm Brussels Salad as a speedy, crunchy compliment. Alternatively, this Brussels and Pear Salad with Manchego is always a favorite.
- Meatballs: I love serving this dish with meatballs! Whether they're beef, turkey, or plant-based, they will help pump up the protein.
- Bread: Garlic bread, crusty Italian bread, or fresh sourdough are always welcome on my table for pasta night!
- Vegan Pumpkin Pasta Sauce: Swap the heavy cream for canned coconut milk or cashew cream.
- Pumpkin Pasta Sauce without cream: For a lower fat alternative to cream, use homemade cashew cream!
- To make homemade cashew cream, pour ⅔ cup boiling water over ⅓ cup raw cashews. Let sit for 30 minutes. When ready to stir in the cream, transfer mixture to a blender and blend until smooth.
- Pumpkin Sage Cream Sauce: Omit the dried oregano and add 1 Tbsp. of finely chopped fresh sage.
- Pumpkin Spaghetti: Instead of spaghetti squash, boil 12 ounces of regular or whole-wheat spaghetti to enjoy with the sauce.
More Spaghetti Squash Recipes to Try:
If you give this recipe a try, snap a pic and tag #dishingouthealth so I can see your creations. I also really appreciate readers taking the time to leave a rating and review! Lastly, follow along on Facebook and Pinterest for the latest recipe updates!
Spaghetti Squash with Pumpkin Pasta Sauce
- Large rimmed baking sheet
- Large skillet
- 2 medium spaghetti squashes (2 lbs. each)
- 4 Tbsp. extra-virgin olive oil, divided
- 1 tsp. kosher salt, divided
- ¼ tsp. cracked black pepper
- ½ cup finely chopped walnuts
- 2 tsp. minced fresh rosemary
- ½ cup finely chopped shallots
- 2 to 3 garlic cloves, minced
- 3 Tbsp. tomato paste
- ½ cup pumpkin puree
- 1 ¼ cups water
- ⅓ cup heavy cream
- ¼ tsp. dried oregano
- Pinch of freshly grated nutmeg (optional)
- Pinch of crushed red pepper flakes (optional)
- ¾ cup grated Gruyere cheese
- ½ cup shredded mozzarella cheese
- Preheat oven to 400°F. Use a sharp chef's knife to carefully slice the spaghetti squash in half lengthwise. Use a spoon to remove the seeds and stringy flesh.Brush the flesh with 1 Tbsp. of the olive oil, and season evenly with ½ tsp. salt and ¼ tsp. black pepper.Arrange the squash halves flesh side-down on a large baking sheet. Roast for 30 to 40 minutes, until fork-tender.
- Meanwhile, heat 1 Tbsp. olive oil in a large skillet over medium. Add walnuts and rosemary; cook for 4 to 5 minutes, stirring often, until the walnuts are lightly toasted and aromatic. Season with a pinch of salt and transfer to a bowl.Add remaining 2 Tbsp. oil to the hot pan. Add shallots and garlic; cook 3 minutes, until soft. Add tomato paste and cook until it turns a deep crimson red, stirring often, about 2 to 3 minutes.Add pumpkin puree, water, heavy cream, oregano, nutmeg, chili flakes (if using) and remaining ½ tsp. salt; gently simmer for 8 to 10 minutes, until the sauce reduces and slightly thickens.
- Remove squash from the oven and turn over to reveal flesh. Spoon the pumpkin pasta sauce evenly into the cavities of each squash boat. Sprinkle Gruyere and mozzarella cheese evenly overtop. Place squash back in the oven for 15 more minutes, or until cheese is melted and bubbly.Sprinkle rosmary walnuts overtop.*To eat, pull the squash strands from the skin of the squash and mix it with the sauce. The squash boats are meant to be used as a serving vessel.