Place the pork ribs in a pot, pour in water, and boil hard for ten minutes.
Drain the ribs and rinse under the tap to remove impurities.
Drop the ribs into a clean pot, cover with water, and add the lemongrass, galangal, garlic, shallots, kaffir lime leaves and two tablespoons fish sauce.
Bring to the boil, lower the heat, cover the pot and simmer until the meat is tender, about an hour and a half to two hours.
Taste the broth occasionally and add more fish sauce, as needed.
Off the heat, stir in a quarter cup of lime juice. Taste the broth. If you want it more sour, add the rest of the lime juice little by little until you get the balance you prefer.
Drop in chili slices, Thai basil leaves and kaffir lime wedges into four bowls.
Divide the pork ribs among the bowls.
Ladle in broth and serve immediately.