Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper. Toss the butternut squash and white onion with olive oil, salt, and pepper, and spread evenly on the baking sheet. Roast for 20 minutes or until the squash is fork-tender.

Cook the pasta according to the package instructions until al dente. Reserve 1 cup of pasta water, then drain the rest and set the pasta aside.

Transfer the roasted squash and onion to a blender or food processor. Add the reserved pasta water, vegetable stock, garlic powder, and oregano. Blend until smooth and creamy.

Toss the cooked pasta with the butternut squash sauce until well-coated.

Serve the pasta topped with grated Parmesan cheese and enjoy!