In a large heavy duty pot, add the olive oil, preheat it over medium heat, add the sausage making sure to break it up as much as you can with a wooden spoon and allow the sausage to cook for about 3 to 4 minutes.
Add the chopped onion and garlic, saute for about 5 minutes, add the stock, tomatoes and Italian seasoning, bring to a boil and allow to simmer for about 15 minutes.
Add the zucchini, simmer for 10 minutes, add the pasta and cook according to package instructions.
Adjust the seasoning to taste, stir in the freshly grated parm and serve!