Bread crumbs Cheese, Parmigiano, grated Clean the mushrooms thoroughly and remove and chop up their stems. Saute onions and garlic in 1/4 cup of olive oil until transparent. Add chopped mushrooms stems, chopped prosciutto, parsley, marjoram, salt and pepper. Saute for about 2 minutes, then add wine. Add bread crumbs until mixture is consistency of mush. Coat mushroom tops with remaining olive oil. Stuff each mushroom with a tablespoon of the mixture, then sprinkle with Parmigiano cheese and bake at 375 F for 3 7 minutes, depending on the size of the mushrooms.