Ingredients

• 0.5 cups reduced-sodium soy sauce
• 0.25 cups rice wine vinegar
• 0.25 cups brown sugar
• 0.25 cups sliced green onions
• 1 tablespoon minced garlic
• 1 tablespoon mustard powder
• 2 pounds flat iron steak
• 2 tablespoons sesame seeds , Optional

Instructions

1. 1 Whisk soy sauce, vinegar, brown sugar, green onions, garlic, and mustard powder together in a bowl; pour into a resealable plastic bag. Add steak, coat with marinade, squeeze out excess air, and seal the bag. Marinate in the refrigerator, 3 to 4 hours.
2. 2 Remove steak from marinade; shake off excess. Discard remaining marinade.
3. 3 Heat a non-stick skillet over medium-high heat. Add steak; cook until outside is seared, about 1 minute per side. Continue cooking 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) for medium.
4. 4 Transfer steak to a cutting board; rest before cutting, 3 to 5 minutes. Sprinkle sesame seeds over steak.

Nutrition per serving