- In a medium saucepan, combine stock, galangal, lemongrass pieces, lime leaves, 2 finely cut chillies, and roughly chopped root and stems of coriander.
- Bring the mixture to a boil. Reduce heat and let simmer for 5 mins. Remove from the heat and allow to stand for around 10 mins.
- Using a colander, strain the solids from the liquid. Discard the solids and return the liquid broth to the heat. Do not boil from this point forward, keep the soup to just below boiling.
- Add coconut cream, chicken, mushrooms, tomatoes, remaining 2 chillies, lime juice, fish sauce and palm sugar. Simmer for around 5 mins, until the chicken is just cooked through.
- Remove from the heat and add in the chopped coriander leaves. Serve in bowls and enjoy!