Combine marinade ingredients in small bowl; mix well. Place beef Flank Steak and marinade in food-safe plastic bag; turn steak to coat. Close bag securely and marinate in refrigerator 6 hours or as long as overnight.
Remove steak from marinade; discard marinade. Place steak on grid over medium, ash-covered coals. Grill, covered, 11 to 16 minutes (over medium heat on preheated gas grill, 16 to 21 minutes) for medium rare (145°F) to medium (160°F) doneness, turning occasionally. Carve steak across the grain into thin slices. Season with salt, as desired.
To broil, place steak on rack in broiler pan so surface of beef is 2 to 3 inches from heat. Broil flank steak 13 to 18 minutes for medium rare to medium doneness, turning once.
Nutrition information per serving, using flank steak, 1/6 of recipe: 167 Calories; 54 Calories from fat; 6g Total Fat (3 g Saturated Fat; 2 g Monounsaturated Fat;) 66 mg Cholesterol; 71 mg Sodium; 2 g Total Carbohydrate; 0.2 g Dietary Fiber; 24 g Protein; 1.5 mg Iron; 9.4 mg NE Niacin; 0.5 mg Vitamin B6; 1.4 mcg Vitamin B12; 4.3 mg Zinc; 27.2 mcg Selenium; 90.8 mg Choline.
This recipe is an excellent source of Protein, Niacin, Vitamin B6, Vitamin B12, Zinc, and Selenium; and a good source of Choline.