Tom Pla Nuea On

1. 1

   Prepare the fish

   Clean the soft-fleshed fish thoroughly under cold running water, removing any blood or impurities. Cut the fish crosswise into steaks about 2-3 inches wide, keeping the skin on as it adds flavor and helps hold the delicate flesh together during cooking. Pat the fish pieces dry with paper towels and set aside. The flesh of pla nuea on is very delicate and can easily become mushy, so handle gently.

   5m

   Tips:

   • • Keep the skin on to help the delicate flesh stay intact
   • • Pat fish dry to reduce splashing when adding to hot broth
   • • Don't cut the pieces too thin or they'll fall apart during cooking
2. 2

   Prepare the aromatics

   Peel and slice the fresh ginger into thin coins. Bruise the lemongrass stalks with the back of a knife or a pestle, then cut into 2-inch pieces to release their aromatic oils. Tear the kaffir lime leaves to release their fragrance. Peel and lightly crush the shallots. Lightly crush the bird's eye chilies to release their heat (keep them whole if you prefer less spice). Clean the cilantro roots thoroughly and pound them lightly. If using young tamarind leaves, rinse them well.

   5m

   Tips:

   • • Bruising the lemongrass is crucial for releasing flavor
   • • Ginger should be sliced, not minced, so it can be eaten or easily removed
   • • Crushing chilies releases more heat - leave whole for milder soup
3. 3

   Build the aromatic broth

   In a large pot, bring the water or fish stock to a boil over high heat. Once boiling, add the cilantro roots, ginger slices, bruised lemongrass, torn kaffir lime leaves, and crushed shallots. Reduce heat to medium and let the aromatics simmer for 5-7 minutes to infuse the broth with their flavors. The broth should become fragrant with the ginger being prominently aromatic. If using shrimp paste, dissolve it in a small amount of hot broth, then stir it into the pot.

   7m

   Tips:

   • • Let the aromatics simmer long enough to fully flavor the broth
   • • Dissolving shrimp paste separately prevents lumps
   • • The ginger aroma should be very prominent
4. 4

   Season the broth

   Add the fish sauce, tamarind paste or juice, and palm sugar to the aromatic broth. Stir well to dissolve the sugar and incorporate the tamarind. Taste the broth and adjust the seasoning - it should taste sour first (from tamarind), then sweet (from palm sugar), then salty (from fish sauce). This is the characteristic flavor profile of tom som. The broth should be assertively flavored as the fish will absorb some of the seasonings.

   2m

   Tips:

   • • Tom som should be sour-dominant, then sweet, then salty
   • • Season the broth well before adding fish
   • • If using tamarind paste, make sure it's fully dissolved
5. 5

   Add vegetables

   Add the cherry tomatoes (or tomato wedges) and mushrooms to the simmering broth. Let them cook for 2-3 minutes until the tomatoes begin to soften and the mushrooms are tender. If using young tamarind leaves, add them now. The tomatoes will add both sweetness and additional acidity to the soup, while the mushrooms provide texture and earthiness.

   3m

   Tips:

   • • Don't overcook the tomatoes or they'll completely fall apart
   • • Mushrooms cook quickly, so watch timing
   • • Young tamarind leaves add authentic Isan sourness
6. 6

   Cook the fish

   Gently slide the fish pieces into the simmering broth, arranging them in a single layer if possible. Add the crushed chilies. Do NOT stir or flip the fish - this is crucial. The gentle heat of the simmering broth will cook the fish evenly, and stirring will cause the delicate flesh to break apart and become mushy. Let the soup simmer gently for 5-7 minutes until the fish is just cooked through. The fish should turn opaque and flake easily when tested with a fork.

   7m

   Tips:

   • • NEVER stir after adding fish or it will become mushy
   • • Maintain a gentle simmer, not a rolling boil
   • • The fish is done when it turns opaque and flakes easily
   • • Be patient and resist the urge to move the fish
7. 7

   Add fresh herbs and final adjustments

   Remove the pot from heat. Taste the soup one final time and adjust seasoning if needed - add more fish sauce for saltiness, tamarind for sourness, or palm sugar for sweetness. Gently add the green onions and sawtooth coriander (culantro) to the pot, letting them wilt in the residual heat. The herbs should remain fresh and vibrant, not cooked through.

   2m

   Tips:

   • • Final seasoning adjustments should be subtle
   • • Fresh herbs added off-heat retain their bright flavor
   • • The soup should have a perfect sour-sweet-salty balance
8. 8

   Serve

   Carefully ladle the soup into serving bowls, ensuring each bowl gets fish, vegetables, and plenty of aromatic broth. Use a large spoon or ladle to transfer the delicate fish pieces without breaking them. Garnish generously with fresh cilantro leaves. Serve immediately while piping hot, alongside steamed sticky rice (the traditional Isan accompaniment) or jasmine rice. Provide extra fish sauce, sliced chilies, and lime wedges on the side for diners to customize their bowls.

   2m

   Tips:

   • • Handle the fish gently when serving to keep pieces intact
   • • Sticky rice is the authentic Isan accompaniment
   • • Serve very hot for the best aroma and flavor
   • • Extra condiments let diners adjust to their taste

• •The key difference between Tom Pla Nuea On and Tom Yum is the prominent use of fresh ginger instead of galangal - this gives the soup a sharper, more citrusy aroma.
• •Soft-fleshed fish (pla nuea on/sheatfish) is prized in Thailand for its sweet, tender flesh and lack of muddy taste. If unavailable, use the freshest catfish, snakehead, or firm white fish you can find.
• •NEVER stir the soup after adding the fish. The delicate flesh will break apart and become mushy. The gentle simmer will cook it evenly without intervention.
• •The soup should taste sour first, sweet second, and salty third - this is the traditional flavor hierarchy of tom som.
• •Fresh tamarind juice or paste is essential for authentic sourness. While lime juice can be substituted, tamarind provides a deeper, more complex sour note.
• •Shrimp paste adds umami depth typical of Isan cuisine. If omitted, increase the fish sauce slightly or add a bit of fermented fish sauce (nam pla ra) for authenticity.
• •Young tamarind leaves are an authentic touch that add gentle sourness and beautiful color. They're optional but worth seeking out at Asian markets.
• •This soup is best enjoyed immediately after cooking while the fish is tender and the herbs are vibrant.
• •Sticky rice is the traditional accompaniment in Isan, but jasmine rice works well too.
• •Keep the broth at a gentle simmer, never a rolling boil, especially after adding the fish.
• •Handle the fish gently throughout cooking and serving to maintain beautiful, intact pieces in each bowl.
• •The soup can be made slightly in advance by preparing the aromatic broth, then adding fish and herbs just before serving.

• •
  sticky-rice
• •
  som-tam
• •
  larb
• •
  gai-yang
• •
  nam-tok
• •
  sai-krok-isan
• •
  khao-niaw

Tom Pla Nuea On is a beloved soup from Isan (northeastern Thailand), reflecting the region's rich freshwater fishing traditions and resourceful use of local ingredients. The name 'pla nuea on' (ปลาเนื้ออ่อน) literally translates to 'soft-fleshed fish,' referring to members of the sheatfish or butter catfish family (Siluridae) found in the rivers and wetlands of the Mekong basin. These fish are highly prized in Thailand for their sweet, tender flesh and lack of the muddy taste common in other freshwater fish, though they're relatively difficult to find and expensive, typically available only in larger markets. The soup showcases the Isan philosophy of bold, clear flavors built from fresh, local ingredients. Unlike the coconut milk-based curries of central and southern Thailand, Isan soups like Tom Pla emphasize clarity of broth and purity of ingredients, allowing each element to shine. The use of ginger (rather than galangal) distinguishes this soup from the more famous Tom Yum and aligns it with the 'tom som' (sour soup) family of dishes. Tom som preparations are characterized by their sour-dominant flavor profile, typically achieved through tamarind or young tamarind leaves, which grow abundantly in Isan. The soup's development reflects the agricultural and ecological realities of northeastern Thailand - a region of rice paddies, rivers, and seasonal flooding where freshwater fish have always been a crucial protein source. The aromatic herbs used (lemongrass, kaffir lime, ginger) grow wild or in home gardens throughout the region. Shrimp paste, another key ingredient, represents Isan's tradition of preserving and fermenting foods for flavor intensity. Tom Pla Nuea On is often enjoyed during the cooler months (October through February) when the fish are particularly sweet and plump. It remains a special-occasion dish in many Isan households due to the premium price of authentic pla nuea on, though similar soups are made with more affordable fish varieties. The dish exemplifies the Isan approach to cooking: simple techniques that honor the quality of ingredients, bold balanced flavors, and dishes designed to be shared family-style with sticky rice.

Authentic Tom Pla Nuea On has several defining characteristics that distinguish it from other Thai fish soups. First, the use of fresh ginger (not galangal) is essential - this is what differentiates it from Tom Yum and categorizes it within the tom som (sour soup) family. The ginger should be prominently aromatic in the finished soup. Second, the flavor balance must follow the traditional tom som hierarchy: sour first (from tamarind or young tamarind leaves), sweet second (from palm sugar), and salty third (from fish sauce). This is not negotiable. The soup should be broth-based and clear, never creamy or thickened - there is absolutely no coconut milk in authentic Tom Pla Nuea On. Shrimp paste (kapi) is traditional for adding umami depth characteristic of Isan cuisine, though some versions may omit it or use fermented fish sauce (nam pla ra) instead. The fish itself - pla nuea on (sheatfish/butter catfish) - is prized for its soft, sweet flesh and is the ideal choice, though other freshwater fish like snakehead (pla chon) or catfish (pla duk) are common substitutes. The cooking method is crucial: the fish must be added gently and NEVER stirred, as the delicate flesh breaks apart easily. The soup should simmer gently, not boil aggressively. Fresh herbs (cilantro, sawtooth coriander, green onions) are added at the end, off heat, and should remain vibrant and fresh-tasting, not cooked. Young tamarind leaves, if available, are an authentic traditional touch that adds both sourness and color. The soup must be served with sticky rice (khao niaw), which is the staple starch of Isan - serving with jasmine rice, while acceptable, is less traditional. The aromatics should be visible in the soup (lemongrass pieces, ginger slices, kaffir lime leaves), though some restaurant versions strain them out for a cleaner presentation. The overall character should be light, aromatic, and refreshing, with the natural sweetness of the fish shining through the sour-sweet-salty broth. This is not a heavy or rich soup - it exemplifies Isan's preference for clear, bright, bold flavors that complement rather than mask the primary ingredients.