This Cantonese classic is easy to make, and takes 30 minutes or less to prepare. This amount of clams will serve two or three generously, but if you're feeding four to six, add another easy dish of steamed egg custard.
Briefly rinse the black beans with water, then drain them and put them in a bowl with 30ml (2tbsp) of hot water. Soak for about 15 minutes, then mash them with a fork and mix in the rice wine.
Rinse the clams under cold running water then drain them in a colander.
Cut the garlic cloves in half and thinly slice them. Slice the bird’s-eye chillies (or other small hot chillies) in half lengthwise, scrape out the seeds and finely chop the flesh. Cut the banana chillies (or other long mild chillies) into thin rounds. Mince the spring onions. Dissolve the cornstarch in 15ml (1tbsp) of cool water.
Place a wok over a high flame, pour in the cooking oil and, when it’s hot, add the garlic and ginger and stir-fry for about 30 seconds, or until fragrant. Add the bird’s-eye chillies and stir, then mix in the black beans and the soaking liquid. Cook until sizzling, then add the clams, the banana chillies and about 60ml (¼cup) of hot water. Stir well, then cover the wok with the lid and turn the heat to medium. Cook for several minutes, or until the clams are cooked, stirring occasionally. If needed, stir in a little more water (the clams will give off a lot of liquid). The clams are ready when the shells open.
Push the clams to the sides of the wok to create a well in the centre. Stir the cornstarch/water mixture, then drizzle it into the liquid in the well. Stir everything together and simmer for about 30 seconds, or until the liquid thickens slightly. Taste for seasonings and adjust, if necessary.
Transfer the ingredients to a serving dish, sprinkle with spring onion and garnish with fresh coriander sprigs.