Preheat your grill to medium heat or desired method of cooking.
Combine mustard powder, smoked paprika, garlic powder, honey, and brown sugar in a bowl and mix well
Place the flank steak cuts on a clean surface and rub the combined ingredients all over the steak. Cover entirely
Cook on the grill for 8 minutes per side or until cooked medium rare. Use an easy-read thermometer to check for doneness
Remove from the heat source and rest for 5 minutes before serving. Enjoy!