1 1/2 lbs. London broil or boneless beef top round steak, or flank steak
Blend Knorr® French Onion recipe mix, Olive Oil and vinegar in large plastic bag or 13 x 9-inch glass baking dish. Add steak; turn to coat. Close bag, or cover, and marinate in refrigerator at least 30 minutes.
Remove steak from marinade, discarding marinade. Grill or broil steak, turning occasionally, until desired doneness.