Place the chicken stock and juice from the rotisserie chicken in a medium-size pot. Bring to a boil and then lower the heat to simmer. Add turmeric powder, lemongrass stalks, and seasonings. Half cover with a lid and let it simmer for 15 minutes. Add coconut milk. If using shredded chicken, add in to let it heat up a bit. Don't let it boil over or your soup will turn frothy. Have a taste and adjust seasoning to your liking. If using large pieces of drumstick or chicken wings, you can add this later when ready to serve
Assembling:
While the soup is brewing, bring a large pot of water to a boil. Trim off the large stems of gai lan. Blanch the gai lan for 5 minutes and then refresh with cold water and set aside. In the same pot, cook the noodle of pasta according to instruction. I like to cook my noodle or pasta separately and not in the soup
Portion the noodle, chicken, and gail lan in an individual serving bowl. Generously ladle the hot soup over. Sprinkle with chopped green onion and serve immediately