Drain the marinated fish from the oil in the jar and arrange them on a plate. Distribute the pickles between them, which have been cut into thin slices, top with the cut into thin crescents onion and a few olives.
Sprinkle with salt, a little black pepper and pour on the vinegar and olive oil. Optionally, you can add olives for decoration.
Add 4-5 tablespoons mayonnaise along the edge of the plate and serve with a sprig of parsley.