Sprinkle flank steak evenly with salt and pepper.
Cook steak in hot oil in large skillet over medium-high heat 6 to 8 minutes on each side or to desired degree of doneness.
Remove steak, and drain, reserving 1 tablespoon drippings in skillet; add garlic, and sauté 1 minute. Add wine, tomatoes, olives, and vinegar; cook 10 minutes or until reduced by half. Stir in parsley.
Cut steak diagonally across grain into thin slices, and serve with tomato mixture. Garnish, if desired.