Tom yum (Lao: ຕົ້ມຍຳ, Thai: ต้มยำ, IPA: [tôm ɲɑm, tôm jɑm], tom yam in the Royal Thai General System of Transcription) is a name for two similar soups originating from Laos and Thailand, respectively. The Royal Lao version includes a pinch of rice in the soup, whereas typical Lao and Thai versions do not include rice as an ingredient. Lao tom yum is relatively unknown outside of Laos, whereas Thai tom yum is perhaps one of the most famous dishes in Thai cuisine. It is widely served in neighboring countries such as Malaysia, Singapore, and Indonesia, and has been popularized around the world.
Tom yum is characterized by its distinct hot and sour flavors, with fragrant herbs generously used. The basic broth is made of stock and fresh ingredients such as lemon grass, kaffir lime leaves, galangal, lime juice, fish sauce and crushed chili peppers.
In Thailand, tom yum is usually made with prawns (tom yum goong), chicken (tom yum gai), fish (tom yum pla), or mixed seafood (tom yum talay or tom yum po taek) and mushrooms - usually straw or oyster mushrooms. The soup is often topped with generous sprinkling of fresh chopped coriander (cilantro) leaves. In Laos, tom yum is typically made with fish or chicken, but freshwater prawns are also available.
The less popular variety of tom yum is tom yum nam khon (Thai: ต้มยำน้ำข้น), where milk is added to the broth. This is not to be confused with tom kha or tom kha gai - where the galanga flavor dominates the soup. Tom yum nam khon is almost always made with prawns, whereas chicken is often used in tom kha. Its other cousin is less well-known outside Thailand - tom klong. Sometimes Thai chili jam (Nam Prik pao, Thai: น้ำพริกเผา) is added: this gives the soup a bright orange colour and makes the chili flavor more pronounced.
Commercial tom yum paste is made by crushing all the herb ingredients and stir-frying in oil. Seasoning and other preservative ingredients are then added. The paste is bottled or packaged, and sold around the world. Tom yum flavored with the paste may have different characteristics to that made with fresh herb ingredients.
Ingredients
4 to 6 servings
* Water or stock -- 6 cups
* Fish sauce -- 1-2 tablespoons
* Kaffir lime leaves -- 4
* Lemongrass, white part of stalk only, crushed --1 stalk
* Galangal (optional), cut into thin rounds -- 2 pieces
* Garlic, crushed -- 2 cloves
* Salt and pepper -- to taste
* Shrimp, peeled and deveined -- 1 1/2 pounds
* Scallions, chopped -- 1/2 bunch
* Straw mushrooms (optional) -- 1 cup
* Limes, juice only -- 2
* Cilantro, chopped -- 1/2 bunch
* Thai chile peppers, sliced into rounds -- 2-3 each
Method
1. Bring the water or stock, fish sauce, lime leaves, lemongrass, galangal, garlic, salt and pepper to a boil in a large pot over medium flame. Reduce heat to low and simmer for 15-20 minutes. Remove from heat and set aside for another 10 minutes to steep. Strain through a fine-meshed sieve and discard solids.
2. Return the stock to a simmer over medium-low heat. Add the shrimp, scallions and mushrooms and continue to simmer over medium-low heat until shrimp is cooked through, 5-6 minutes.
3. Stir in the lime juice, cilantro and chilies, adjust seasoning and serve.
Variations
* Tom Kha Kung: Substitute coconut milk for half or all the water or stock.
* Tom Yum Gai: Substitute thinly sliced chicken for the shrimp.
* Tom Yum Hed: A vegetarian variation. Eliminate the shrimp and double the amount of mushrooms.
* Add the shrimp shells from peeling the shrimp to the simmering stock for extra flavor.
* Straw mushrooms are usually found canned. You can substitute thinly sliced button mushrooms if you like, or omit the mushrooms altogether.
* Sliced bamboo shoots can be added if you like.
* If kaffir lime leaves are unavailable, zest the limes before juicing them and use the zest instead.
