Heat oven to 350°F.
Combine chicken, garlic, oregano, salt and pepper, vinegar, olive oil, prunes, olives, capers with juice, and bay leaves. Cover and marinate overnight.
Arrange chicken in shallow baking pans and spoon marinade over evenly.
Sprinkle chicken with brown sugar. The printed method also directs the cook to pour white wine around the chicken.
Bake 50 minutes to 1 hour, basting frequently with pan juices, until chicken is done.
Transfer chicken, prunes, olives, and capers to a serving platter. Moisten with pan juices, garnish with parsley or coriander, and serve remaining pan juices separately.