To Prep
Pound the white pepper, garlics, shallots and chillies in a mortar and pestle until smooth. Add the remaining paste ingredients and pound until smooth.
To Cook
Pour water into a pot and bring to boil. Add in the paste and simmer for a few mins.
Add in the vegetables, from the longest cooking time to the ones that cook fast. Cook until almost done.
Add in the prawns and cook until all ingredients are cooked through. Add the fish sauce to taste.
Remove from heat, add lemon basils and serve hot.