Tom Kha Gai (Thai Coconut Chicken Soup)

One of my first experiences with Thai food was a bowl of Tom Kha Gai soup at a restaurant called Tara Thai in Rockville, Maryland back when I was in high school.  It was my first introduction to the use of coconut milk in soup, its sweetness meshing nicely with the savoriness of fish sauce; the brightness of cilantro, lemongrass and lime; and the heat of red curry paste and Thai chilis.  As I started eating more and more Thai food, I realized that many variations of Tom Kha Gai soup are far too sweet and missing the necessary spice and acid to balance out the natural sweetness of the coconut milk.  During my travels in SE Asia I tried Tom Yum soup and realized that Tom Kha Gai soup isn't the only delicious Thai soup out there.  Now when I go out for Thai I tend to alternate between ordering Tom Kha Gai and Tom Yum, depending on my mood, but I still have a special place in my heart for a really nice bowl of Tom Kha Gai soup.

This bowl of Tom Kha Gai soup was really nice and had lots of spice to it to balance the sweetness.  If you don't like spice, I would cut down on the amount of curry paste or on the number of dried Thai chilis.  In the past I have always made the soup with green curry paste instead or red, but we were out of green this time so I decided to use red instead.  In my admittedly limited experience, green curry paste tends to make a soup that is a little more floral and a little less outright spicy.  But both are delicious.  The red curry paste also gives the soup an orange tint, rather than the more traditional milky white broth from the coconut milk.  Strictly speaking, the curry paste isn't necessary, but it does add some extra complexity and some heat to the soup.  If you aren't using the curry paste, you need to use more lemongrass, galangal (or gingern like I used here, although galangal is definitely preferable) and kaffir lime leaves than I used here to give the soup the same depth of flavor.  You will end up with a soup that is in some ways more delicate, not to mention less spicy, than the recipe I have included here.  With the inclusion of the curry paste and the straw mushrooms, this soup almost reminds me of a cross between Tom Kha Gai and the more traditionally spicy Tom Yum soup. 

Recipe after the jump!

Tom Kha Gai (Thai Coconut Chicken Soup)

INGREDIENTS
One 14-ounce can coconut milk

1 cup chicken stock

4 slices fresh galangal or ginger, each roughly 1/4-inch thick
1 lemongrass stalk, tough outer portion removed tender portion only, chopped and crushed in mortar
5 fresh or dried kaffir lime leaves, torn inhalf (or 1 tablespoon grated lime zest)

8 dried Thai chilis, roughly chopped
3/4 pound boneless and skinless chicken breast, thinly sliced

1 14-oz. can straw mushrooms, drained
5 tbsp Thai or Vietnamese fish sauce
2 tbsp palm sugar or granulated sugar
1/3 cup fresh lime juice
1 tsp Thai red curry paste
1/4 cup coarsely chopped cilantro 

In a wok or large pot, combine 1 cup of the coconut milk with the ginger, lemongrass, dried Thai chilis, lime leaves, and curry paste.  Stir to combine and bring to a boil.  Add the chicken stock, chicken, mushrooms, fish sauce, and sugar.  Reduce the heat to medium, and simmer until the chicken is white and firm, about 4 minutes.  Add the remaining coconut milk and heat to an energetic simmer, about 3 minutes.  Add lime juice.  Stir to combine.  Season to taste with s&p or additional lime juice.

Ladle the soup into individual bowls.  Garnish each bowl with the cilantro.  Serve immediately.