Start by cooking your pasta el dente reserving 2 cups of the pasta water.
In the mean time make the sauce in the saute pan over medium high heat in the olive oil saute the sausage until beginning to brown before adding the garlic and onion saute until the onion and garlic are soft and fragrant. Deglaze the pan with the chicken stock waiting until it evaporates before adding the pasta water. Then simmer the sauce until it thickens, about 15 minutes.
Add the el dente cooked pasta. Then in the same pasta water cook the broccoli until fork tender. Mash some of the broccoli and add to the pasta. Adjust your seasoning. Top with grated parmesan cheese and Italian parsley.