Heat the oil in a frypan and brown chicken breasts 4 minutes on each side. Set aside.
Add spring onions, chilli, celery and capsicum then fry, stirring constantly, 5 minutes or until vegetables are softened. Add mushrooms and cook 2 more minutes.
Return the chicken to the frypan and stir in garlic, fennel seeds, coriander, cumin and turmeric. Cook 1 minute. Add tomatoes with their juice and coconut milk. Bring to a simmer, cover and simmer 5 minutes.
Stir in the water chestnuts and lime juice. Serve with white rice, garnished with fresh coriander.