This delicious one-skillet supper is super speedy—basically, everything you'd want in a weeknight dinner!
In cast-iron skillet, cook seasoned steak in oil over medium-high, 3 to 4 minutes per side for medium-rare. Add butter, hoisin, and ginger. Cook for 1 minute, basting steak with butter. Transfer steak to cutting board. In skillet, cook bok choy over medium-high, stirring, for 4 minutes; season. Slice steak. Serve with bok choy. Drizzle bok choy with hot sesame oil.