Korean Beef Bok Choy

Cook the rice according to package directions. Meanwhile, cut the steak diagonally across the grain into 1/4-in.-thick slices. Heat 1 tsp oil in a large nonstick skillet over medium-high heat. Add half the meat and cook until no longer pink, about 30 seconds. Transfer to a medium bowl. Repeat with 1 tsp oil and the remaining meat. Add 2 Tbsp stir-fry sauce to the bowl with the beef. Wipe out the skillet and heat the remaining 2 tsp oil over medium-high heat. Add the bok choy and cook, tossing for 1 minute. Add 3 Tbsp water to the skillet, cover and cook for 1 minute. Uncover, add the remaining stir-fry sauce and cook until the bok choy is just tender, 1 minute more. Return the meat and any juices to the skillet and cook until heated through, about 30 seconds. Serve with the rice and sprinkle with crushed red pepper, if desired.