1.In a medium bowl, combine chicken, juices, garlic, oregano, cumin, chilli and oil. Stand for 10 minutes.
2.Drain chicken; reserve marinade. On a heated oiled grill plate (or grill or barbecue), cook chicken for about 3-5 minutes each side, or until browned all over and cooked through.
3.On the same grill plate (or grill or barbecue), cook corn, orange and onion for about 2-5 minutes, or until tender.
4.Place reserved marinade in a small saucepan; bring to a boil. Reduce heat, simmer, uncovered, for about 2 minutes or until thickened slightly.
5.Serve chicken with corn, orange and onion, drizzled with marinade.