Hunan Spicy Fish with Pickled Cabbage

Suancai yu — sour vegetable fish — is a dish that has moved from regional Sichuan-Chongqing origins to become one of the most popular restaurant dishes across all of China in the past two decades. The combination of mild, slippery fish, sour pickled vegetables, and a broth that is simultaneously spicy and tart has proven broadly appealing across regional palates, and dedicated suancai yu chains have spread to virtually every Chinese city.

The fish most commonly used is grass carp (caoy) or black carp, sliced thinly on the bias to create long, thin pieces that cook quickly and remain tender. The fish is first coated in a marinade of egg white, cornstarch, Shaoxing wine, salt, and sometimes white pepper — a technique called velvetising that protects the fish during cooking and gives it a smooth, silky texture. The pieces should be thin enough to cook through in one to two minutes of gentle poaching.

The suancai — pickled mustard greens, not to be confused with the milder napa cabbage version found in other preparations — is the sour element. These are fermented whole mustard greens that have been pickled with salt and sometimes chilli; they have a pronounced sour flavour and a slight crunch even after cooking. The pickled greens are stir-fried first in the wok with ginger, garlic, pickled chilli (paojiao), and dried chillies, then stock is added to make the broth. The fish slices are lowered in gently and poached just until opaque.

The finished dish is served in a large bowl: fish pieces layered over the cooked suancai, the broth poured over the top, and then a final dressing of hot oil poured over dried chilli flakes and Sichuan peppercorn scattered across the surface. The hot oil blooms the aromatics dramatically and adds a crackling sound at the table.

The balance of sourness from the pickled vegetables, heat from the chilli, mild numbing from the peppercorn, and the clean flavour of the fish is the reason the dish has travelled so successfully across China's varied regional preferences.