Cut the leeks into slices, keeping only the white part. Peel the celery. Slice the celery and the onion.
Chop the chestnuts coarsely.
Heat the olive oil and butter in a large pan. Add the vegetable and chestnut. Cook for a few minutes, stirring regularly.
Add the white wine and let it boil down slightly before adding the vegetable broth. Season with salt and pepper and let cook for 15 minutes on medium heat.
Slice the parsley. Peel the apple or apple chips and cut into dices/slices.
Whip the cream until stiff
Puree the soup, adding just a little bit of broth or water if needed.
Sit the cream into the soup shortly before serving. Sprinkle with parsley and apple slices/dices.