In a large, deep skillet, heat 1 tablespoon of olive oil to the skillet. Add the onion and sausage and cook over high heat, breaking up the sausage with a spoon, until lightly browned and cooked through. Add butternut squash, 1/4 cup of your favorite pomedoro sauce, and 1 tablespoon of butter to skillet and let flavors blend.
Meanwhile, in a large pot of boiling salted water, cook the pasta according to package directions. Drain the pasta, reserving 1 cup of the cooking water. Add the pasta to the skillet along with the reserved cooking water and the cheese and cook over moderately high heat, stirring, until the sauce is thick and creamy, 1 to 2 minutes. Transfer the pasta to a bowl, sprinkle with additional parmesan cheese and parsley and serve.