1tablespoonclear rice wine(can also use Shaoxing wine, though clear rice wine yields a cleaner, milder flavor)
First, prepare the Chinese broccoli. Wash them thoroughly in a big bowl of water, agitating the water and rubbing the leaves to loosen any dirt. Then allow them to soak for about 5-10 minutes to allow the dirt/sand to settle at the bottom of the bowl. Repeat twice, for a total of three washings.
Trim away any tough ends. Larger, thicker gai lan stems can get tough at the bottom of the stalk, so trim a ¼-inch off the ends, and use a paring knife or peeler to remove the outer layer of the bottom stem (which can be too fibrous to eat), similar to what you would do with asparagus. Then slice on a diagonal into 2 to 2 ½ inch pieces.
If desired, mix the salt, sugar, white pepper, and msg (if using), so you can add them to the vegetables all at once. When you’re stir-frying, you want everything close at hand so you can focus on building wok hei.
Heat your wok over medium-high until it’s just smoking. Spread the oil around the perimeter of the wok. Add the ginger slices, and cook for 10-15 seconds, or until they’re fragrant and just starting to caramelize (this will happen very quickly if your heat is high enough).
Add the garlic, followed immediately by the Chinese broccoli. Using a scooping motion, stir-fry with your wok spatula for 10 seconds to coat everything in the oil and evenly distribute the ginger and garlic.
Increase the heat to high. Add the clear rice wine around the perimeter of the wok.
Push all of the Chinese broccoli into the middle of the wok in a small pile. Cover the wok for 1 minute. Steam will cook the vegetables, and the sides of your wok should superheat.
Remove the wok lid. Gripping the wok by the handle, use your spatula to drag the Chinese broccoli around the sides of the wok. This will create a searing, wok hei effect. Next add the salt, sugar, white pepper and msg (if using).
Stir-fry for another 30 seconds, or until the gai lan has reached the desired tenderness. If the vegetables look too dry at this point, add a splash of hot water or chicken stock. Serve.