Marinate Flank Steak overnight in lime juice and garlic, then chop up a zesty pico de gallo while the beef is on the grill. Be sure to slice steak against the grain for max tenderness. Ingredients 1 beef Flank Steak (about 1-1/2 pounds) 12 flour tortillas (6-inch diameter), warmed Marinade: 2 tablespoons fresh lime juice