For the porcini on chestnut spaghetti, clean the porcini and cut into small cubes.
Sauté finely chopped onion in oil until translucent. Add the mushroom cubes and sauté. Season with salt, pepper and nutmeg and deglaze with rosé wine. Let simmer for a while.
Meanwhile, cook the chestnut spaghetti in salted water. Fry the chestnuts, peel and chop coarsely. Arrange the porcini mushrooms on the chestnut spaghetti and sprinkle with the pieces of chestnut.