Clean and trim the mushrooms. Halve the mushrooms and chop the oyster mushrooms. Peel onion and dice very finely. Heat the oil in a pan and sauté the onion for 1-2 minutes.
Add the mushrooms and fry for approx. 4 minutes. Prepare noodles in boiling salted water according to package instructions. Wash parsley, dab dry and put 1 stalk aside for garnishing. Cut remaining leaves into fine strips.
Remove the mushrooms from the pan. Sear the oyster mushrooms in the pan for 1-2 minutes, then add them to the mushrooms. Dust the gravy with flour. Add cream and stock while stirring and let simmer for 3-4 minutes.
Drain the pasta and let it drain in a sieve. In the meantime cut salami into wide strips. Season the sauce with salt and pepper. Add spaghetti, salami, parsley and mushrooms to the sauce and mix well.
Arrange the spaghetti and garnish with the remaining parsley.