Boil the chicken cubes in the chicken broth until they are fully cooked.

Decrease flame to low, and add salt, white pepper, soy sauce and vinegar.

Cut open the green chillies with a longitudinal cut and scrape off all of the seeds. None should be left in it. Now, thinly slice the green chillies adjacent to the longitudinal cut. Add the fine chilli pieces to the broth.

Mix the cornstarch with little water to make a paste. Bring the broth to boil and add the cornstarch to it, properly mixing it in.

Decrease the flame so as to just simmer, squeeze the juice of the lemons and add to the soup. Add the boiled rice to it now as well.

Sprinkle lemongrass and add the fish sauce. Enjoy!