Thai Coconut Lemongrass Chicken Soup (Tom Kha Gai)


We had a frost.

I had plans to get this post out at the beginning of the week, but the first frost of the year, which my weather report told me was coming Friday night, showed up early.  Monday night, to be precise.*  Thankfully, I had spent Monday morning harvesting all the remaining eggplants and tomatoes, so the most vulnerable (and to me, the most precious) of the vegetables escaped harm.  But the rest of the week saw me in full-on triage mode – harvesting the rest of the frost-tender plants, salvaging what I could, and preserving the damaged goods as fast as I could go.

Thus, a bit of a delay on the blogging front.  But the harvest has been salvaged, and I’m back at it.  And I’ve (finally) got Thai food!


This, you guys, is why I grow lemongrass.**




Fragrant with coconut, ginger, and the distinctly tropical smell of lemongrass, this soup is at once bright and fresh, and deeply comforting.  Piles of citrus-y lemongrass simmer in a coconut-rich broth, along with healthy amounts of ginger, garlic, and hot peppers.  Chicken quarters, browned and simmered in the same broth, lend still more richness.  And traditional Thai ingredients like fish sauce, cilantro, and lime finish the dish with both depth and brightness.



This is Southeast Asian soul food.  Mom’s homemade chicken soup – rich and velvety, filled with the vibrancy of the tropics.


As the morning air crackles with the first tinges of winter, and as the first logs leave the woodpiles to bring warmth to our home, this is the dish I want to eat.  It warms like winter and tastes like sunshine.



*Note to self:  Find a better weather report.

**I’m sure there are other very delicious things to do with lemongrass, but our craving for this soup always seems to outlast my lemongrass supply.


Thai Coconut Lemongrass Chicken Soup (Tom Kha Gai)

Yields about 8 cups, or 6 to 8 servings, depending on whether you serve it over rice

Adapted heavily from an Instructables post

Lots of notes:
Lemongrass, when grown in long-season, tropical climates, grows a big thick stalk, about 1 inch in diameter.  So the lemongrass sold in stores is usually just a short portion (maybe 10 inches long) of this thick stalk.  It will not look like the grassy bundle shown here.  Note: your measurements may differ if you’re using store-bought lemongrass.  The original recipe calls for 4 stalks of store-bought lemongrass (actually 2, but I doubled the recipe), so I’d go with that unless you have a grassy bundle like mine.

If you’re interested in growing lemongrass yourself, I got my seeds here.  I started my plants indoors 3 weeks before our last frost date, and planted them out 5 weeks later.  Aside from a bit of weeding and watering, I basically ignored them until just before our first frost, when I chopped off the grass stalks at the base, cut them up into 1 to 2 inch pieces, and froze them in gallon-sized zip-top bags.  I got an average of 5 cups of chopped lemongrass from each of my plants.  If you’re growing in a hotter, longer-season climate, you may get more.

This recipe works well with pre-cooked, shredded chicken meat.  Just skip the third paragraph in the instructions, and add your chicken meat at the end, cooking just to warm it through.  You’ll need about 2 cups (13 ounces) of cooked, chopped meat.

I added chopped eggplant to the batch of soup in the photos, simply because I was swimming in eggplant.  It’s not included in the recipe because I don’t think it adds anything to the soup, but if you have a bunch of eggplant to use up, go ahead.  I used the same amount of eggplant as mushrooms (4 cups), in a 1 inch dice.

The original recipe calls for galangal – a ginger relative with a distinctive floral taste.  I substituted ginger, but if you can find galangal, I’m sure it would be fantastic.

Fish sauce is a thin, dark brown liquid made from fermented fish paste.  Don’t be afraid of the fermented fish paste bit – it lends a delicious depth and richness to the soup, and is one of the key flavors in Thai cooking.  It’s also quite salty, so don’t adjust the salt level of the soup until after you’ve added the fish sauce.

A note on sourcing Thai ingredients:  An Asian grocery store is your best bet for availability, but if you don’t have one nearby, lots of major grocery chains carry a decent selection of international foods.  (In my area, Wegmans does a good job with this.)  And if you don’t see something, ask!  Sometimes stores can add an unusual ingredient to their next produce order at little or no extra cost.  Lemongrass and galangal both freeze well, so you could buy a large amount and freeze it for later use.

3 cups (135 grams) sliced lemongrass
3 cloves garlic, roughly chopped
3-inch piece of ginger, peeled and roughly chopped (1/4 cup)
4 serrano chiles, sliced
1/2 teaspoon whole coriander seed
5 cups chicken broth
2 14.5-ounce cans (1 3/4 cups) coconut milk
2 teaspoons vegetable or peanut oil
1 3/4 pounds of bone-in, skin-on chicken pieces (I used 2 leg quarters)
2 medium onions, diced small
4 cups (12 ounces) sliced mushrooms (any type, I used regular creminis)
1 lime, zested and juiced
1/4 cup fish sauce
2 teaspoons brown sugar
1 cup (loosely packed) chopped cilantro
salt, to taste
cooked rice or crusty bread, to serve

Combine lemongrass through coconut milk in a large saute pan and bring to a boil.  Reduce heat to medium-low, cover, and simmer.  While broth is simmering, prepare your other ingredients.

After 30 minutes, strain the broth through a fine meshed sieve, discarding the solids (you can press on them while they’re in the strainer to get a bit more liquid out).

Rinse out the now-empty pan, return it to the stove over medium-high heat, and pour in the 2 teaspoons of oil.  Generously salt both sides of your chicken pieces.  When the oil is hot but not smoking, add the chicken pieces, skin side down.  Brown both sides of the chicken, then return the broth to the pan.  Add the chopped onions, bring the broth to a boil, then reduce heat, cover, and simmer again for 40 minutes, or until the chicken is cooked through (the timing will depend on the size of your cuts.  I used rather large leg quarters, so your cooking time may be less).

When the chicken is cooked through, remove it to a plate to cool and add mushrooms through brown sugar to the broth.  Simmer for about 10 minutes, or until the mushrooms are cooked.  While the mushrooms are cooking, shred the chicken into bite-sized pieces, discarding the skin and bones.*

Once the mushrooms are cooked, return the chicken to the pan (if you’re using pre-cooked chicken meat, add it here, and cook just to warm through).  Turn off the heat, and stir in the cilantro and 1/2 of the juice from your lime.  Taste for seasonings, and add more lime juice, fish sauce, or salt, if you want.

My favorite way to serve this soup is over a small amount of cooked rice, which gives it the body of a stew.  It also goes well with some nice crusty bread.  Enjoy!


*Or saving them for broth – I keep a big zip-top bag going in the freezer for chicken and veggie scraps, and make a batch of broth whenever it gets full.

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