Place first 8 ingredients in a 2-gal. zip-top plastic bag, and squeeze bag to combine. Add steak; seal bag, and chill 30 minutes to 1 hour and 30 minutes. Remove steak from marinade, discarding marinade.
Preheat grill to 400° to 450° (high) heat. Grill steak, covered with grill lid, 9 minutes on each side or to desired degree of doneness. Remove from grill; squeeze juice from lemon over steak. Let stand 10 minutes. Cut across the grain into thin slices.
Herb-Marinated Chicken Breasts: Substitute 1 3/4 lb. skinned and boned chicken breasts for flank steak. Proceed with recipe as directed, grilling chicken 7 minutes on each side or until done. Prep: 15 min., Chill: 30 min., Grill: 14 min.