Rinse the herbs and soak in a bowl of warm water to soften. Remove and drain well.
Wash the fish and pat dry. Score on both sides of the fish and rub with a pinch of salt and pepper. Coat with some cornflour. Deep-fry in hot oil until cooked through and golden. Remove and drain.
Leave 2 tablespoons oil in the wok and fry ginger, garlic and shallots. Add carrot, mushrooms, fresh chicken stock and seasoning and bring to a boil. Reduce heat to low and simmer for 20 minutes until fragrant.
Thicken the gravy with a little cornflour mixture. Pour over the fish.
Sprinkle with shredded chilli and coriander. Serve hot.