Preheat oven to 400 degrees F and grease a baking sheet with oil or cooking spray.
Slice the bok choy in half and place on the baking sheet, cut side up.
Drizzle each half with 1/2 tsp of olive oil, then sprinkle a pinch each of garlic powder, red pepper flakes, salt and pepper.
Roast in the oven for 10-15 minutes or until it becomes crispy.
Allow the bok choy to cool for 5 minutes before removing it from the pan. Enjoy as a side dish or incorporated into a stir fry.