Bring a medium saucepan of water to the boil for the pak choy. Crush or finely chop the garlic. Finely chop the onion. Trim the beans. Thickly slice the pak choy, keeping stems and leaves separate. Thinly slice the spring onion. Combine the garlic, oyster sauce, Chinese barbecue seasoning, 1 tsp sugar and ½ tsp soy sauce in a bowl and season with pepper.
Step 2 — Brown pork mince
Heat 2 tsp oil in a medium deep frypan over high heat. Cook the onion and pork mince, breaking up the lumps with a spoon, for 3-4 mins until browned. Remove from the pan. Reserve the frypan.
Step 3 — Cook pak choy
Meanwhile, cook the pak choy stems in the pan of boiling water for 2 mins. Add the pak choy leaves and cook for 30 secs or until tender. Remove the pak choy from the water with tongs and put in a sieve to drain, then transfer to a serving plate and cover to keep warm. Reserve the pan of water for the dumplings (do not drain the water).
Step 4 — Cook beans
Heat 2 tsp oil in the reserved frypan over high heat. Cook the beans, stirring occasionally, for 3-4 mins until blistered and just tender.
Step 5 — Cook dumplings
While the beans are cooking, bring the water in the reserved pan to the boil. Cook the dumplings in the boiling water for 4 mins. Drain. Transfer to a serving plate.
Step 6 — Finish pork and beans
Add the pork mixture and oyster sauce mixture to the beans and cook, stirring, for 1 min or until combined, then transfer to a serving plate. Drizzle 1 tsp soy sauce over the pak choy. Scatter the spring onion over the dumplings. Serve the pork and beans, dumplings and pak choy with the sriracha sauce (sriracha is a hot chilli sauce; use more or less to taste).