Heat avocado or vegetable oil (1 tablespoon) in a wok or large non-stick pan over medium heat. Add the garlic (4 cloves), ginger (2 tablespoons), and red pepper flakes (1/4 teaspoon), and cook until fragrant -- about 2 minutes. Be sure to stir constantly so ingredients don't burn. Add soy sauce (2 tablespoons) and 1 tablespoon water.
Add bok choy (4 bunches) and toss to thoroughly coat. Cover with a lid and cook for 2-4 minutes, until tender. Remove lid, stir, and continue to cook for 3 minutes, or until most of the liquid has evaporated and the stalks have softened to your liking.
Place boy choy on a platter and drizzle with sesame oil. Option to sprinkle sesame seeds on top. Enjoy!
Notes
Oil. You want a mellow flavored oil that can take a lot of heat. I use avocado oil, vegetable oil works as well.
Baby bok choy is sweeter and more tender than bok choy, so I strongly suggest using it. Pay special attention to rinsing this veggie as it holds on to dirt--I like to remove the base and clean each individual leaf (dirt often pools near the base).
Completely dry you bok choy! Otherwise, it will splatter when it touches the oil.