1. Mix salted soya beans sauce, finely chopped chilli, chopped ginger and lime well together. Prepare to serve with fish head.
2. Cut half the straw mushrooms. Follow by the pound chilli, shallot, coriander root, galangal, lemongrass and shredd kaffir lime leaves.
3. Boil chicken broth, add galangal, lemon grasss, kaffir lime leaves, chilli, shallot and coriander root. Boil for 5 minutes.
4. Season with fish sauce, salt and stir well. When water start boiling, add fish head down. (Do not stir) close the lid and boil boil for 5 minutes.
5. Add mushrooms and cover with the lid for 1 minute. Then turn off the gas, add lime just a little and stir for a while.