In a saucepan, bring water to a boil and add the diced butternut squash. Cook for about 8-10 minutes, until tender. Drain and set aside.
In a large pot, cook the penne pasta according to package instructions until al dente. Reserve 1 cup of pasta water, then drain.
In the same pot, heat olive oil over medium heat. Add the chopped onion and sauté until translucent (about 5 minutes). Then add the minced garlic and cook for an additional 1-2 minutes until fragrant.
In a blender, combine the cooked butternut squash, vegetable broth, coconut milk, nutmeg, thyme, salt, and pepper. Blend until smooth and creamy. If the sauce is too thick, add reserved pasta water a little at a time to reach desired consistency.
Return the blended sauce to the pot with the onion and garlic. Stir well and heat through, then add the cooked penne pasta. Toss until all the pasta is coated with the creamy butternut squash sauce.
Taste and adjust seasoning with additional salt, pepper, or nutmeg if desired.
Plate the creamy butternut squash penne in bowls, garnishing with fresh parsley and grated Parmesan cheese if desired.
Notes
Serve with grated Parmesan cheese for added flavor.