Vietnamese Sour Fish Soup (Canh Chua Cá) — Tamarind-Scented Mekong Soup

• 600 gcatfish steaks or fillets (cut into 4 large portions)
• 3 gfine sea salt
• 1 gground white pepper
• 50 gseedless tamarind pulp
• 240 mlboiling water (for extracting the tamarind)
• 1.25 lwater
• 1 tbspneutral cooking oil
• 2medium shallots (thinly sliced)
• 3 clovegarlic (finely chopped)
• 45 mlfish sauce
• 20 ggranulated sugar
• 250 gpineapple (peeled, cored, and cut into bite-size wedges)
• 300 gripe tomatoes (cut into wedges)
• 120 gokra (trimmed and sliced diagonally)
• 150 gelephant ear stem (also called bạc hà or taro stem; peeled and sliced diagonally)
• 120 gmung bean sprouts
• 8 sprigrice paddy herb (roughly chopped)
• 10 gsawtooth coriander (thinly sliced)
• 3scallions (cut into 3 cm lengths)

Instructions

1. 1

   Season the catfish with 3 g fine sea salt and 1 g ground white pepper, then let it stand for 10 minutes while you prepare the vegetables. This short seasoning firms the surface slightly and helps the fish stay intact in the simmering broth.

2. 2

   Place the tamarind pulp in a heatproof bowl and pour over 240 ml boiling water. Mash thoroughly with a spoon for 2 minutes, then strain through a fine sieve and press firmly to extract a smooth sour tamarind liquid.

3. 3

   Heat the oil in a 3 l pot over medium heat and cook the shallots for 2 minutes until fragrant and lightly softened. Add the garlic and cook for 30 seconds, stirring constantly so it scents the oil without browning harshly.

4. 4

   Pour in 1.25 l water, the strained tamarind liquid, fish sauce, and sugar, then bring the broth to a gentle boil. Add the pineapple and tomatoes and simmer for 5 minutes so their sweetness rounds out the tamarind acidity.

5. 5

   Lower the heat to a steady simmer and slide in the seasoned catfish portions in a single layer. Cook for 6 to 8 minutes, turning the fish only once, until the flesh is opaque and just flakes at the thickest point.

6. 6

   Add the okra and elephant ear stem and simmer for 2 minutes, then add the bean sprouts, rice paddy herb, sawtooth coriander, and scallions. Turn off the heat after 30 seconds so the herbs stay fresh, then serve the soup immediately in deep bowls with plenty of vegetables and broth.