Put a pot of salted water on to boil for the pasta. While you wait, heat oil in a large frying pan with a knob of butter and sauté 3 cloves of garlic and one diced brown onion, season with some sage, marjoram or thyme. Add chopped mushrooms and sauté for another 2–3 minutes.
Meanwhile, add the pappardelle to the boiling water and cook until al dente (fresh pasta should not take more than 3 or 4 minutes).
Add pasta water to the mushrooms and let it reduce for 1 minute. Season with salt and pepper. When the pasta is ready, drain it, stir some cream into the mushroom sauce, heating together briefly. Add the butter and a little of the cooking water if the pasta seems dry. Serve sprinkled with parsley and parmigiano reggiano.