c-az's Asian Flank Steak

1 2 to 2 ½ lb beef flank steak
½ cup soy sauce
¼ cup lemon juice
¼ cup minced onion
¼ cup packed brown sugar
2 tablespoons toasted sesame oil
1 tablespoon grated fresh ginger
1 tablespoon minced fresh garlic

Place flank steak in a resealable plastic bag; add soy sauce, lemon juice, onion, brown sugar, sesame oil, ginger and garlic. Seal bag; turn to coat evenly. Refrigerate 1 to 24 hours, or freeze.
Preheat grill to medium-high.
Remove steak from bag, reserving marinade. Grill for 10 to 15 minutes for medium rare (135 degrees), turning once halfway through grilling. Meanwhile, simmer marinate over medium heat until reduced by half; keep warm.
Let steak stand 5 minutes.

To serve, slice meat across the grain into very thin slices. Drizzle with reduced marinade.