Clean the Chinese broccoli then cut the stalks into roughly 3cm lengths, peeling them if necessary. Tear or cut the leaves into large pieces.
Assemble the prepared broccoli and the roast pork, along with the oyster sauce, soy sauce, stock or water and sugar. Crush the garlic to a somewhat coarse paste with the salt - either by pounding it using a pestle and mortar or finely chopping it with a knife.
Heat a well-seasoned wok and add the oil. When it is fiercely hot, add the garlic and stir-fry briskly until it is coloured then add the assembled ingredients and continue to stir-fry for a few moments until the broccoli is cooked.
Sprinkle with the pepper and serve with steamed rice.
