Halve the carrot lengthwise and thinly slice. Thickly slice the pak choy, keeping the stems and leaves separate. Peel the ginger and cut into very thin matchsticks or finely grate (see cooking tip). Pick the coriander leaves, then finely chop the coriander stems. Thinly slice the spring onion.
Step 2 — Make stock
Crumble the stock cubes into a heatproof jug. Add 1 tbs soy sauce, 1 tsp sugar and 1L (4 cups) boiling water and stir to combine. In a separate bowl, whisk 1 egg and 1 tsp soy sauce.
Step 3 — Make broth
Heat the sesame oil in a medium saucepan over medium-high heat. Stir-fry the ginger and coriander stems for 30 secs or until fragrant, but not coloured. Add the stock, increase the heat to high and bring to the boil.
Step 4 — Cook dumplings
Reduce the heat to medium-high. Add the carrot to the broth and cook for 2 mins. Add the pak choy stems and dumplings and cook, at a gentle simmer, for 2 mins. Add the pak choy leaves and cook for a further 1 min or until wilted. Season with freshly ground black pepper and remove from the heat.
Step 5 — Cook omelette
Meanwhile, heat 2 tsp oil in a small frypan over medium-high heat. Add the egg mixture and swirl to coat the base of the pan. Cook for 1 min or until just set, then loosely roll up the omelette in the pan. Transfer to a board.
Step 6 — Get ready to serve
Cut the omelette into strips. Divide the dumplings and soup among bowls. Scatter over the omelette, spring onion and coriander leaves to serve.