📝 About This Recipe
Experience the vibrant heartbeat of Central Thailand with this iconic hot and sour shrimp soup. This aromatic masterpiece balances four essential flavors—spicy, sour, salty, and sweet—using a fragrant base of lemongrass, galangal, and kaffir lime leaves. It is a light yet deeply complex broth that showcases the freshness of succulent prawns and the earthy depth of traditional Thai aromatics.
🥗 Ingredients
The Broth Base
- 5 cups Chicken stock or water (unsalted stock is preferred for better salt control)
- 3 pieces Lemongrass stalks (bottom 5 inches only, bruised and cut into 2-inch segments)
- 1 3-inch piece Galangal (sliced into thin rounds)
- 6-8 pieces Kaffir lime leaves (torn slightly to release essential oils)
- 4-6 pieces Thai bird's eye chilies (bruised; adjust for heat preference)
- 2 pieces Coriander roots (cleaned and bruised)
Main Ingredients
- 1 lb Large prawns or shrimp (peeled and deveined, tails left on for presentation)
- 1.5 cups Oyster mushrooms (torn into bite-sized pieces; straw mushrooms also work)
- 1 piece Roma tomato (cut into wedges)
- 1/2 piece White onion (sliced into wedges)
Seasoning and Finishing
- 2 tablespoons Thai chili paste (Nam Prik Pao) (adds color and a smoky sweetness)
- 3-4 tablespoons Fish sauce (adjust to taste for saltiness)
- 4-5 tablespoons Fresh lime juice (added at the very end to preserve brightness)
- 1 teaspoon Palm sugar (to balance the acidity)
- 1/4 cup Fresh cilantro (roughly chopped for garnish)
- 3 tablespoons Evaporated milk (optional; for the 'Tom Yum Nam Khon' creamy version)
👨🍳 Instructions
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1
Prepare the aromatics: Peel the outer layers of the lemongrass, cut off the woody top, and use the back of a knife to bruise the bottom stalks before slicing diagonally.
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2
In a large pot, bring the chicken stock or water to a rolling boil over medium-high heat.
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3
Add the lemongrass, galangal, kaffir lime leaves, coriander roots, and bruised chilies to the boiling water. Let this simmer for 5-8 minutes until the broth becomes highly fragrant.
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4
Stir in the white onions and mushrooms. Cook for 2-3 minutes until the mushrooms begin to soften.
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5
Add the Thai chili paste (Nam Prik Pao) and stir well to ensure it dissolves completely, giving the broth its signature orange hue.
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6
Gently drop in the shrimp and the tomato wedges. Cook for only 2-3 minutes—just until the shrimp turn pink and opaque. Do not overcook or they will become rubbery.
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7
Season the soup with fish sauce and palm sugar. Stir gently to combine.
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8
If you prefer the creamy version, stir in the evaporated milk now and let it come back to a very gentle simmer for 30 seconds.
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9
Turn off the heat entirely. This is crucial: adding lime juice to boiling soup can make it taste bitter.
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10
Stir in the fresh lime juice. Taste the broth; it should be a bold harmony of spicy, sour, and salty.
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11
Remove the large pieces of galangal and lemongrass if desired, or leave them in for an authentic rustic look (just remind guests not to eat them!).
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12
Ladle the soup into warm bowls, ensuring everyone gets several shrimp and mushrooms, and garnish generously with fresh cilantro.
💡 Chef's Tips
Always use fresh galangal over ginger; the flavor profile is piney and citrusy, which is essential for authenticity. Never boil the lime juice; the high heat changes the chemical structure and creates a dull, bitter flavor. For a deeper flavor, use shrimp with heads on. Sauté the heads in a little oil first to release the orange fat before adding the stock. If you can't find kaffir lime leaves, a bit of lime zest is a temporary fix, but the leaves provide a unique floral aroma that is hard to replicate. Adjust the number of bird's eye chilies based on your spice tolerance—crushing them more releases more heat.
🍽️ Serving Suggestions
Serve with a side of steaming jasmine rice to soak up the flavorful broth. Pair with a Thai Omelet (Kai Jeow) to provide a savory, fatty contrast to the sour soup. A cold Thai Iced Tea or a crisp Lager beer works beautifully to cut through the spice. Follow with a cooling dessert like Mango Sticky Rice to soothe the palate. Serve in a traditional Thai hot pot with a charcoal burner to keep the soup piping hot at the table.