Tom Yum Soup

First, prep all components to enable fast, uninterrupted cooking: Peel 340g shrimp, leaving tail segments intact for presentation, and set peeled shrimp aside in a bowl; reserve all shrimp shells and heads for broth. Remove tough outer layers from 2 lemongrass stalks, cut into 5cm lengths, and smash lightly with the flat side of a knife to release aroma. Slice 20g galangal into 3mm thick rounds, tear 8 kaffir lime leaves after removing their tough central vein, lightly smash 4 bird's eye chilies, drain and halve 200g straw mushrooms, cut 1 Roma tomato into 4 wedges, squeeze 60ml fresh lime juice, and measure out 3 tbsp fish sauce, 1 tbsp grated palm sugar, and 2 tbsp roasted chili paste. This prep takes approximately 10 minutes.

Pour 1200ml chicken broth into a 3L stainless steel stockpot, add the reserved shrimp shells, smashed lemongrass, galangal slices, torn kaffir lime leaves, and smashed chilies. Place the pot over medium-high heat until the broth reaches a rolling boil (5-7 minutes), then reduce heat to medium-low, cover the pot with a lid, and let simmer for 10 minutes to fully extract herbal, briny flavor from the aromatics and shrimp shells.

After 10 minutes of simmering, set a fine-mesh stainless steel sieve over a large heatproof glass bowl, pour the simmered broth through the sieve to catch and remove all shrimp shells, lemongrass, galangal, lime leaves, and chili pieces. Discard the spent, flavorless solids, then pour the clear, fragrant infused broth back into the stockpot, and return it to medium heat to bring back to a gentle simmer (about 2 minutes).

Once the strained broth returns to a gentle simmer over medium heat, add the halved straw mushrooms and tomato wedges, and cook for 2 minutes to soften slightly. Then add the reserved peeled raw shrimp, stir gently with a wooden spoon, and cook for exactly 3 minutes just until the shrimp turn opaque pale pink and curl into a tight C-shape; do not overcook, as shrimp will develop a tough, rubbery texture if heated longer than 3 minutes.

Reduce stovetop heat to low, then stir in 3 tbsp fish sauce, 1 tbsp grated palm sugar, and 2 tbsp roasted Thai chili paste (Nam Prik Pao), stirring continuously for 30 seconds until the sugar and chili paste fully dissolve, turning the broth a warm golden-orange color. Turn off the heat entirely, then pour in the 60ml fresh lime juice, stirring once to incorporate; never boil the soup after adding lime juice, as high heat will make the lime taste bitter and dull its bright sour flavor.

Ladle the finished soup evenly into 4 warm ceramic serving bowls, ensuring each bowl gets 3 shrimp, a portion of mushrooms, and tomato wedges. Top each bowl with 1 teaspoon of chopped fresh cilantro, and serve immediately while piping hot, with extra lime wedges and small dishes of fish sauce on the side for diners to adjust flavor to their taste.