Cut into thin slices, celery pour salted water. Add the olive oil, onion, tomato paste * and olives. Boil over low heat until celery is tender (about 15-20 minutes). We remove from the heat and add the chopped parsley. The dish can be served hot and cold. * The original recipe is 2 tbsp tomato paste, but I put more, 5-6, depending on how much sauce I have.