Preheat your oven to 400°F. Spread the cubed butternut squash onto a baking sheet, drizzle with olive oil, and season with sage, thyme, salt, and pepper. Roast for 25-30 minutes, or until the squash is fork-tender.
Meanwhile, cook your pasta according to the package directions. Reserve about ½ cup of the pasta water before draining, if needed to thin the sauce later.
Heat a large skillet over medium-high heat. Add the ground chicken and cook for 7-10 minutes, breaking it apart as it browns. Once fully cooked, transfer it to a plate. In the same skillet, add the diced red onion and sauté for 3-4 minutes, until softened.
Transfer the roasted butternut squash to a blender along with the chicken stock and garlic. Blend until completely smooth and creamy.
Pour the butternut squash sauce into the skillet with the onions and let it simmer for 2–3 minutes. Taste and season with additional salt and pepper if needed.
Stir the cooked ground chicken back into the sauce, then add the half-and-half and white wine vinegar. Mix until everything is well combined and heated through.
Add the cooked pasta and toss until evenly coated. If the sauce is thicker than you'd like, stir in a splash of the reserved pasta water until it reaches your desired consistency.
Serve topped with freshly grated Parmesan cheese and red pepper flakes, if desired. Enjoy!