1.Place celery, onion, carrot, coriander roots, garlic, star anise, peppercorns, salt and chicken in large saucepan. Fill with enough cold water to just cover chicken and place lid on pan. Bring to boil to high heat, then reduce heat to medium-low. Simmer gently for 45 minutes until chicken is cooked.
2.Combine green onions, ginger and vegetable oil in mixing bowl. Season with salt and set aside until required.
3.Remove chicken from its stock and place on board to rest.
4.Strain stock and pour 4 cups into medium saucepan with rice. Cover with lid. Place over medium heat and cook for 12 minutes until tender. Use fork to stir through coriander leaves.
5.Remove meat from chicken bones, slice into pieces and place on top of rice. Spoon over ginger sauce and top with green onions.