Choy Sum Stir-Fried with Ham and Ginger

Like celery, bok choy and choy sum add crunch and color. But it’s quite a challenge to focus a dish on the vegetable alone. Although easy to cook, it is difficult to cook just right.

Here’s why it took twelve tests to find a simple, effective stir-fry: Choy sum’s texture was uneven when cooked entirely uncovered or covered—it needed both; high heat resulted in a scorched taste; multiple ingredients hid the choy character; sauced, the satiny surface of the stalks turned slippe