Prep the ingredients by cutting the pancetta into small pieces, slice the onion and mushrooms, and mince the garlic.
Once the ingredients are prepped, bring a large pot of water to a boil, add sufficient salt then toss in the pasta. Cook according to the directions on the package.
While the pasta is cooking, heat the extra virgin olive oil over medium high heat in a large sauté pan. Add the pancetta and cook for a few minutes, until it begins to color.
Add the onions, then add the garlic and continue to sauté for a few minutes. Next, add the mushrooms. Remember to keep an eye on the strozzapreti and stir occasionally. Add more oil if the mushroom mixture is too dry, and continue to cook and stir occasionally.
Add salt and pepper to taste, along with the chopped parsley and cook until the mushrooms are ready and the water released has evaporated.
Pour in the cream, and bring to a boil, then cover and turn the heat down just to keep the sauce hot. The mushroom sauce is ready.
When the strozzapreti are cooked, drain them and add directly to the sauce in the pan. If you drain the pasta, reserve a cup of water. I remove the pasta with a pasta strainer, so all the water is left in the pot. Toss the strozzapreti with the mushroom sauce until well mixed adding the reserved pasta water if the pasta is too dry. Add grated cheese if using, and mix again. Serve immediately as is, or with a sprig of parsley to garnish. See notes for other serving options.