Pick the coriander leaves and finely chop the stems. Crush or finely chop the garlic. Thinly slice the spring onion on an angle. Thinly slice the chilli, removing the seeds if less heat is desired. Crumble 3 stock cubes* into a heatproof jug, add 750ml (3 cups) boiling water and stir to dissolve.
Step 2 — Fry aromatics
Heat 1 tbs oil in a medium saucepan over medium-high heat. Add the coriander stems, garlic, half the spring onion and half the chilli (long chillies are typically mild, but if you prefer zero heat, omit it and serve at the table for those who like a chilli-kick). Cook, stirring, for 2 mins or until fragrant.
Step 3 — Add stock
Add the stock, 1 tbs soy sauce and 1 tsp sugar to the aromatics. Scrunch the lime leaves to release the flavour and add to the pan. Season with pepper and bring to the boil. Reduce the heat to medium-low and cook for 5 mins to develop the flavour.
Step 4 — Chop vegetables
Meanwhile, halve the carrot lengthwise and thinly slice. Coarsely chop the pak choy, keeping the stems and leaves separate.
Step 5 — Cook dumplings
Increase the heat to medium. Add the carrot to the soup and cook for 2 mins. Add the pak choy stems and dumplings and cook for a further 3 mins.
Step 6 — Get ready to serve
Stir the pak choy leaves into the soup and cook for 1-2 mins until the pak choy leaves are wilted and the dumplings are heated through. Remove the lime leaves (they're too tough to eat). Divide the dumplings and soup among bowls. Scatter over the coriander leaves, remaining spring onion and remaining chilli to serve.