Prepare the bok choy. Wash and dry the bok choy, then slice lengthwise and lightly coat with sesame oil.
Grill the bok choy. Heat a BBQ or grill pan over medium-high heat. Grill the bok choy cut-side down until charred, then flip and cook until the stems are tender but still crisp. Remove and set aside.
Mix the slurry. Stir the cornstarch and water together in a small bowl until smooth.
Make the sauce. Heat the chili oil, oyster sauce, garlic, and sugar in a small pan, stirring until combined and fragrant.
Thicken the sauce. Add the cornstarch slurry and cook briefly, stirring, until the sauce thickens and looks glossy.
Serve. Spoon the sauce over the grilled bok choy and serve immediately.
Notes
Use the nutrition card in this recipe as a guideline.