Step 1

Place oil in a wok over medium-high heat, add onion and stir-fry until transparent but not coloured (1 minute). Add garlic and ginger and stir-fry until fragrant (20-30 seconds), then add pork and stir-fry until browned (3-5 minutes). Add sugar and ¼ tsp salt, stir to dissolve sugar (30-40 seconds), then add stock, chilli bean sauce, sweet sauce and dark soy sauce, and stir until liquid has reduced (1-2 minutes). Add vinegar and simmer, stirring occasionally, until meat is tender, sauce is thick and coats the meat (3-5 minutes). Keep warm.

Step 2

Cook noodles in a large saucepan of boiling water until al dente (3-5 minutes). Season 4 serving bowls with a little Chinkiang vinegar (about ½ tsp) and oil (about 1 tsp). Add noodles and toss to coat. Top with stir-fried pork, cucumber, hot pepper condiment to taste and coriander leaves.