Bring a large pot of salted water to a rolling boil. Add the pasta and cook until al dente, approximately 10 minutes. Drain, rinse briefly and transfer to a large bowl.
While the the pasta is cooking, heat the olive oil over medium heat in a large Dutch oven or heavy bottom saucepan. Brown the sausage on both sides, in batches if necessary to avoid overcrowding the pan. Remove the sausage from the pan and set aside.
Turn the heat down to medium-low. If the bottom of the pan seems dry, add an additional 1/2 - 1 tablespoon of olive oil. Add the onions along with a pinch of salt and cook for several minutes until they are soft, stirring periodically, then add the garlic and cook for an additional 1-2 minutes. If at any point the bottom of the pans begins looking like it’s going to burn, add 1-2 tablespoons of water and scrape the brown bits back into the onions and garlic. (note: brown bits are good; black bits are bad.) After the garlic has cooked, add the mushrooms and cook until they're caramelized and have slightly reduced down in size, 3-5 minutes.
Add the white wine to the pot and use a spatula to scrape up any brown bits and incorporate them back into the vegetables. Once the liquid from the wine has reduced almost completely, add the chicken stock. Turn the heat up to medium, and allow the liquid to reduce down by about half.
Add the mushroom mixture along with the liquid from the pan to the pasta bowl, along with 1 tablespoon cream. Toss everything together until evenly combined, seasoning with salt and pepper to taste (I used 1/2 teaspoon each of salt and pepper). Toss in the additional tablespoon of cream if desired.
Serve pasta topped with a healthy sprinkling of chopped parsley.
If you plan to serve white wine with the pasta, that's a great choice for using in the recipe since it will create a natural pairing. Don't use a sweet wine, but something citrusy is ok, like a New Zealand Sauvignon Blanc. A dry chardonnay is almost always a safe choice. If you don't consume alcohol, it can be omitted entirely.