Tom Kah Recipe

prepare aromatics

Smash the lemongrass stalks lightly with the back of a knife and cut into 2–3 pieces each. Thinly slice the galangal (or ginger) and tear the kaffir lime leaves into large pieces to release oils.

In a medium pot over medium heat, combine the coconut milk and chicken or vegetable stock. Stir gently to combine, then add the prepared lemongrass, galangal slices, kaffir lime leaves, and sliced white onion.

Bring the mixture to a gentle simmer (do not boil vigorously to prevent coconut milk splitting). Reduce heat to low and simmer gently for 10 minutes to infuse the coconut with the aromatics.

While the base simmers, prepare mushrooms and protein. Slice mushrooms and if using chicken, cut into thin bite-sized strips so they cook quickly.

After the base has simmered 10 minutes, add the mushrooms and chicken (if using) to the pot. If using tomatoes, add them now as well. Add up to 1/2 cup water if the soup seems too thick. Increase heat slightly and simmer until mushrooms are tender and chicken is cooked through, about 4–6 minutes depending on thickness.

In a small skillet over medium-low heat, warm the Thai red chili paste for 30 seconds to a minute to bloom flavors (optional). Add the minced garlic and cook briefly until fragrant, about 20–30 seconds (do not brown).

Stir the warmed chili paste and garlic into the soup. Add thinly sliced fresh red chilies if you want extra heat. Simmer everything together for 1–2 minutes to marry flavors.

Remove the pot from heat. Stir in fish sauce (or soy sauce), lime juice, and sugar. Taste and adjust: add more fish sauce for saltiness, lime juice for tang, or sugar for balance. Add salt if additional seasoning is needed.

Ladle soup into bowls and garnish with chopped cilantro and green onions. Discard the larger pieces of lemongrass and galangal if desired before serving.

Serve hot. Provide extra lime wedges and chili paste at the table for guests to adjust seasoning and heat to taste.