Shell and devein the prawns, reserving the shells. Rinse the shells and place them in a large saucepan with the chicken stock.
Bruise the lemon grass stalks (gently pressing down on them with the blunt side of a cooking knife). Add them to the broth along with half of the lime leaves. Bring to a boil, then reduce heat to low, and simmer gently until the lemon grass changes color, and the stock becomes fragrant, about 5 minutes. Strain the stock and return to the saucepan. Discard the solids.
Return the stock to a simmer, and add the mushrooms and prawns. Cook until the prawns are pink. Stir in the fish sauce, lime juice, 2 tablespoons green onion, cilantro, red chilies, and remaining lime leaves. Taste, and adjust seasoning if necessary. The soup should be sour, salty, spicy and hot. Garnish with remaining green onions.
Calories From Fat
% Daily Value*
Total Fat 0g
Saturated Fat 0g
Trans Fat 0g
Dietary Fibers 0g
* Percent Daily Values are based on a 2,000 calorie diet.
* Nutrition information is estimated based on the ingredients and cooking instructions as described in each recipe and is intended to be used for informational purposes only. Please note that nutrition details may vary based on methods of preparation, origin and freshness of ingredients used.