Tom Yum Soup Recipe

Prepare aromatics

Smash the lemongrass stalks with the back of a knife and cut into 2–3 pieces each. Peel and slice galangal. Tear the kaffir lime leaves once to release oils. Halve the shallot. Lightly bruise the chilies (leave whole for milder heat or slice for more).

In a large pot, combine 6 cups water and 2 cups stock. Add the prepared lemongrass, galangal slices, kaffir lime leaves, halved shallot, and bruised chilies. Bring to a gentle boil over medium-high heat.

Reduce heat to medium-low and simmer, uncovered, for 10–15 minutes to infuse flavors. Taste the broth for aromatic strength; simmer up to 20 minutes if you want a stronger herb flavor. Do not boil aggressively after adding aromatics to preserve freshness.

After simmering the aromatics, strain or use a slotted spoon to remove large pieces (optional: leave kaffir leaves for presentation). Return the clear infused broth to the pot and keep it at a gentle simmer.

Stir in 1 tablespoon Thai red chili paste (or Tom Yum paste) until dissolved. Add 3 tablespoons fish sauce and 1 teaspoon palm sugar, stirring to combine. Taste and adjust: more fish sauce for saltiness, more sugar to balance, or more paste for heat/color.

Remove the pot from heat briefly and stir in 3 tablespoons fresh lime juice. (If you plan to add coconut milk, add it now and gently rewarm the broth without boiling.)

Return the pot to a low simmer. Add the mushrooms and tomato wedges. Simmer 2–3 minutes until mushrooms begin to soften and tomatoes slightly collapse.

Add the peeled, deveined shrimp to the simmering broth and cook 2–3 minutes until they turn pink and opaque. Do not overcook shrimp — they cook quickly.

Stir in sliced scallion greens and roughly chopped cilantro leaves, saving a small amount of cilantro for garnish.

Taste the finished soup and adjust seasoning: add a little more fish sauce for saltiness, a splash of lime juice for brightness, or extra chili paste for heat.

Ladle the Tom Yum into bowls. If using, drizzle 1/4 cup coconut milk into the soup for a creamy Tom Yum Nam Khon variation and gently swirl. Garnish with remaining cilantro, a sprinkle of toasted rice powder if desired, and lime wedges on the side.

Serve immediately while hot. Estimated total cooking time is short — shrimp will be tender and the broth fragrant and bright.