Remove the stems from the spinach, wash the chervil and chop finely, cut the apple into thin strips. Peel the onion and slice into rings. Mince the smoked haddock. Remove the rind from the Chavignol and cut it into slices, as thin as possible. In a bowl, successively mix the vinegar, salt, pepper, and olive oil. Arrange the spinach, the haddock, the apple strips, the onion slices, and the thin slices of Chavignol. Season with the vinaigrette and sprinkle with chervil.