Finely shred the cabbage and finely chop the carrot, capsicum, and spring onion whites so everything cooks quickly and evenly once the wok is hot.

Mix the cornflour with a few tablespoons of water in a small bowl, stirring until completely smooth with no lumps, and set aside.

Heat the oil in a wok over high heat and stir-fry the cabbage, carrot, and capsicum for a couple of minutes until they soften slightly but still have crunch.

Add the chopped garlic, ginger, spring onion whites, and green chili to the wok and stir-fry until fragrant.

Pour in the vegetable stock along with the soy sauce and vinegar, and bring the mixture to a boil.

Lower the heat and simmer the broth gently so the vegetables finish cooking through and the flavors of the garlic, ginger, and sauces come together.

Give the cornflour slurry a quick stir to recombine it, then pour it into the simmering broth while stirring continuously until the soup visibly thickens.

Stir in the black pepper and salt, then taste and adjust the seasoning until the broth has a bold, peppery edge.

While the soup simmers, deep-fry the thin noodles in hot oil in a separate pan until they turn golden and crisp, then drain on a paper towel.

Ladle the hot soup into bowls and top with the crispy fried noodles and remaining spring onion greens.