Break the leaves off and soak in a large container, then rinse all the dirt off.
Cut the leaves from the stems, then cut the larger stems in half, then chop into sections about ⅓ of an inch wide. Cut the leaves into strips about the same size.
Pour a little oil in a frying pan, then put in the cut stems and stir fry for about a minute.
Add the chopped leaves, gently stir-frying for another three minutes or so. (It's important not to overcook the choy.) Sprinkle with salt.