- 4 Large freshwater Prawns with heads and front claws attached if at all possible (Or just use any type of shrimp)
- 1 cup canned Straw Mushrooms (washed and cut in half lengthwise)
- 1 inch piece Galangal root (sliced into very thin pieces)
- 1 stalk Lemongrass (bottom portion only – root end and first 2 outer layers removed – cut diagonally into 3–4 pieces)
- 1/4 Small Brown or Yellow Onion (thinly-sliced)
- 1 large scallion (cut into 1 inch pieces, root end and any browning tips discarded)
- 3–4 leaves Culantro (cut into 1 inch pieces) – if unavailable, use Cilantro instead
- 4 Small Thai dried Hot Chilis (dried puya or dried Chinese tien tsin ‘facing heaven’ chilis can substitute)
- 4–5 fresh Kaffir Lime leaves (whole leaves, stems left in)
- 4 small Cherry Tomatoes
- 2 Thai Hot Chilis, 1 red or orange and 1 green (the tiny ones known as ‘rat dropping chilis in Thai) (seeds in, finely crushed) – if unavailable, used habanero
- 1 Tbsp. Thai Roasted Chili Sauce (Nam prik pao)
- 1/4 cup Evaporated milk (unsweetened)
- 2 tsp. Fish Sauce
- 2 tsp. Coconut Sugar
- 1 1/2 Tbsp. fresh Lime juice
- 1/2 Tbsp. tamarind paste (TFD addition, replace with lime juice for original )
- 1 tsp. oyster sauce or to taste (TFD change, original was Kosher salt – TFD strongly endorses Megachef brand from Thailand as the best in the world!)
- Finely crush the 2 Thai hot chilies using a mortar and pestle.
- Break open the 4 dried Thai hot chilies just a little using the pestle. They should be left whole.
- Measure and assemble the rest of the ingredients, and have them ready for quick use in the soup.
- Boil 2 cups of water or chicken stock (TFD strongly prefers chicken stock) in a small pot or pan. Add the galangal, lemongrass, onion, and smashed fresh chilies. Boil for 1 minute.
- Add the shrimp to the water or stock. If they are not covered, then add a little more liquid. Add the mushrooms, then bring the soup back to a boil. Boil for 2 minutes, stirring carefully. Then add the coconut sugar.
- Next add the fish sauce, oyster sauce, tamarind paste and lime juice. Stir in well and boil for 30 seconds.
- Taste the broth. It should be spicy, a little salty, and a little sour. You can add more red chili (spicy), fish sauce (salty), or lime juice (sour) to balance the flavor as you like it.
- Add the kaffir lime leaves, green onion, culantro, and tomatoes.
- Add the Nam Prik Pao sauce and stir it in well until it is completely melted and blended with the soup.
- Add the condensed milk to the soup and carefully stir in until well blended.
- Remove the shrimp, tomatoes, and a few nice mushroom pieces and set them on a plate. Spoon the rest of the ingredients into a small bowl that is just barely big enough.
- Fill the bowl with broth to just cover everything, then carefully arrange the shrimp on top, with heads and legs sticking out. Add in the tomatoes and mushrooms wherever they look nice.
- Garnish with fresh kaffir lime leaves. Float a few whole Thai hot chiles, some cut culantro leaves, coriander leaves, and a little raw green onion on top.
- Tom Yum is normally served as a shared dish. Each person should have a small plate of steamed Thai Jasmine rice. The soup is spooned onto the rice with your own spoon, one spoon at a time, mixed in and eaten. If you prefer not to eat Thai style, then serve in smaller bowls, one for each person.