For the mushroom powder, process the dried cep mushrooms until finely ground, combine them with the pepper and herbes de Provençe.
Cut the duck breasts lengthways into 3 mm (⅛ inch) wide strips. Lay out the strips of duck two by two on top of each other, alternating layers of fat and lean. Cut the zucchini into strips using a vegetable peeler. Lay the strips of zucchini on top of the du