Score the meat against the grain (this means make cuts about 1/4 inch deep). Place flank steak and all ingredients in a shallow bowl or baggie. Let sit in a refrigerator for a minimum of 2 hours but no more than 8 hours.
Once ready to cook, make sure to heat up the grill until it is nice and HOT (about 400 degrees). Place flank steak on the grill and let cook for about 4 minutes or until the meat easily releases from the grill. Flip over and cook for another 4-6 minutes.
Let meat rest for about 5 minutes while wrapped in some aluminum foil. Cut flank steak in thin strips. Cut against the grain in a diagonal angle.