Make the marinade by mixing together the sugar, salt, fish sauce. lemon grass and cornflour slurry. Mix in the chicken, allow to marinate for 20 minutes.
Blanch the celery in boiling water for 3-4 minutes, drain and set aside.
Heat a large frying pan with 1 tablespoon oil over high heat. Fry the chicken until evenly brown, 3-4 minutes. Add just enough water to cover 1/2 of the chicken. Simmer for 10 minutes or until the chicken is cooked through. Set aside.
Heat the same pan with 1 tablespoon oil over high heat. Stir-fry the lemon grass, shallot, spring onions, garlic and onion until soft, about 3-4 minutes. Add the celery, chicken, fish sauce, sugar and chilli oil, stir well to combine and serve.
I tried the recipe as it was and found it far too salty from the amount of fish sauce quantity advised. The second time I used only tablespoon of fish sauce in the sauce and added one tablespoon of lime juice. That worked better for me. For a bit of crunch I added some unsalted cashew nuts at the end of cooking, making this a hybrid Thai/Chinese dish. - 16 Jun 2013