Perfect Flat Iron Steak

Place steak inside a large resealable bag. Stir olive oil, garlic, parsley, rosemary, chives, red wine, salt, pepper, and mustard powder together in a small bowl.

Pour marinade over steak in the bag. Press out as much air as you can and seal the bag. Marinate in the refrigerator for 2 to 3 hours.

Heat a nonstick skillet over medium-high heat. Sear and cook the steak in the hot skillet for 3 to 4 minutes on each side for medium rare, or to your desired degree of doneness. An instant-read thermometer inserted into the center should read 130 degrees F (54 degrees C) for medium rare.

Discard the marinade. Allow the steaks to rest for about 5 minutes before serving.