1. In a bowl, mix together the orange, lemon and lime juices, onion, garlic, sauce /chilli powder, cumin, salt and sugar.
2. Pour half of this mixture into a large plastic resealable bag /box.
3. Cut chicken into slices of 1-centimetre thickness and add it into the citrus mixture. Leave it in the fridge to marinate for at least 2 hours.
4. Put the remaining sauce into a blender (optional) and place it in the refrigerator.
5. Heat a non-stick pan and fry the chicken. When almost done, add the marinade to the pan and simmer for a few minutes.
6. Remove the chicken and cut into thin strips.
7. Cut the salad, green onion, celery and oranges and mixed in a large bowl.
8. Mix the salad with the remaining sauce, and add the chicken slices on top.