In a large dish with a cover, place chicken, then pour over Sesame-Ginger broth, ginger, orange juice and zest, onions and sugar. Stir until meat is well-coated.
Marinade in refrigerator for 6 hours, turning over from time to time.
20 minutes prior to cooking, remove meat from refrigerator and let sit at room temperature.
Preheat barbecue on high.
Drain chicken breasts and place on hot barbecue grill. Reduce heat to medium. Cook around 4 to 5 minutes on each side or until meat is well done.
Transfer cooked chicken breasts to a serving platter and garnish with cilantro and sesame seeds. Serve immediately.
