Asian Flat Iron Steak Recipe

Whisk soy sauce vinegar brown sugar green onions garlic and mustard powder together in a bowl; pour into a resealable plastic bag. Add the steak coat with the marinade squeeze out excess air and seal the bag. Marinate in the refrigerator 3 to 4 hours.

Remove steak from marinade and discard remaining marinade.

Heat a non-stick skillet over medium-high heat; cook steak just until outside is browned and seared about 1 minute per side. Continue to cook until desired doneness is reached about 5 minutes more per side. An instant-read thermometer inserted into the center should read 140 degrees F (60 degrees C). Remove skillet from heat and allow steak to rest before cutting 3 to 5 minutes. Sprinkle sesame seeds over steak.