15 Minute Mongolian Beef is full of flavor and super easy to make. In the time it takes to cook rice, you can have delicious restaurant quality Mongolian beef ready to serve on top.
Slice the flank steak against the grain into long strips. Put the strips into a medium-size mixing bowl.
Stir in soy sauce, hoisin sauce, sesame oil, brown sugar, garlic, ginger, and red pepper flakes until meat is evenly coated.
Heat a heavy skillet over high heat. Add in the olive oil and sear the meat until desired level of doneness is reached (2 to 3 minutes for medium rare).
Top with green onions (optional). Serve hot over cooked rice or rice noodles.