Trim ends of the Chinese broccoli. Line up the Chinese broccoli with the stems facing same direction. Cut the stalks in half to separate the thick stems from the leaves.
Add 1″ of water to a wok, pot or large saute pan and bring to a simmer on medium heat. Layer in the broccoli stems at the bottom of the wok and layer the leaves on top of the stems. You want the thick stems closer to the bottom of the pan so that they will cook faster. Steam for 3 minutes. Use tongs to lift the leaves to a serving plate. Check the stems to make sure they are cooked – they should be easily pierced with a fork. Plate the stems when they are done.
Discard the remaining water in the wok and wipe dry with a towel. Return wok to the stove and add in the cooking oil and ginger, garlic and chile pepper. Turn the heat to medium-low. Once the oil in the wok begins shimmering, cook for another 15 seconds (take care not to burn the aromatics). Stir in the miso water, soy sauce and sesame oil and cook another 15 seconds. Pour sauce over the Chinese broccoli.