2 tbsp fermented black beans, rinsed and crushed with the back of a spoon (or use 100g black bean sauce instead)
1 tbsp Shaohsing rice wine
3 tbsp toasted sesame oil
3 tbsp light soy sauce
2 spring onions, shredded
1 small handful coriander, leaves picked
Wash the fish in cold running water. Pat dry with kitchen paper, then slash 3-4 slits into the skin on both sides. Season all over with salt and ground white pepper. Place ginger slices in the slits of the fish and inside the cavity.
Place the fish on a plate that fits inside your wok. In your wok place a pudding bowl upside down and pour water to come halfway up. Place the wok on the heat and bring the water to a boil.
Pour the rice wine over the fish, put the plate onto the upside-down bowl and place the lid of the wok on top. Steam on high heat for 8-9 mins, then leave to rest.
While the fish is cooking, make the black bean sauce. Add the groundnut oil to a hot wok or frying pan. When it starts to smoke, add the garlic, ginger and beans (or use 100g ready-made black bean sauce) and stir-fry for a few secs. Add the rice wine, sesame oil and light soy sauce, then bring to the bubble.
Carefully remove the fish (you can keep it on the plate that you cooked it on). Garnish with the spring onions and coriander, then drizzle over the black bean sauce and serve with rice.