1 1/2 lb Flank Steak (1 Piece)
1/2 md Sweet Onion; Thinly Sliced
And Separated Into Rings
1/3 c  Lemon Juice
1 lg Clove Garlic; Split
1 tb Sugar
1/2 ts Salt
2 tb Soy Sauce

Pull off any membrane from the steak and trim away any surface fat. Score
the steak, 1/8-inch deep, on both sides in a diamond pattern. In a plastic
bag or glass dish large enough to hold the steak, combine the onion, lemon
juice, garlic, sugar, salt, and soy sauce. Add the steak and close the bag
tightly if using and turn the meat to coat thoroughly. Marinate for 1 to 2
hours at room temperature, 6 to 8 hours in the refrigerator. Drain off and
reserve the marinade. Grill the steak 3 to 5 inches above hot coals until
rare to medium-rare, 3 to 5 minutes on each side. Meanwhile, heat the
remaining marinade. Remove the steak to a cutting board and cut, in thin
slices, across the grain, slanting the knife slightly. Serve the meat with
the marinade.