For an extra layer of flavor, consider adding a pinch of red pepper flakes to the sauce. If the sauce becomes too thick, add a splash of pasta water to loosen it up. Conversely, if the sauce is too thin, simmer it for a few more minutes to reduce it. Freshly grated Parmesan cheese is highly recommended for the best flavor and texture. For a vegetarian option, substitute the sausage with mushrooms or other vegetables.