• Place steak and vinegar in 13- x 9-inch glass or ceramic pan; turn to coat evenly. Cover with plastic wrap and refrigerate, turning occasionally, for at least 1 hour.
• Preheat grill; grease grate well. Remove steak from marinade. Grill steak for 8 minutes per side or until instant-read thermometer temperature registers 145°F when inserted into thickest part. Transfer to cutting board with well to catch juices; let stand for 5 minutes.
• Meanwhile, place spinach on dinner plates or large serving platter. Cut steak into thin slices diagonally; arrange over spinach. Drizzle with collected meat juices. Season with salt and pepper to taste. Drizzle with oil. Cut shavings from Parmesan cheese and scatter over top. Serve with bread on the side.

Tip: Instead of barbecuing, the flank steak can be broiled for about 8 minutes on each side if desired.

Recipe Provided by Chef Sharon Sanders