1 ½ lb flank steak
salt and pepper to season
12 butter lettuce leaves
½ cup thinly sliced white or yellow onion
1 cup shredded mozzarella
1 cup diced tomatoes
1. Coat grill pan with cooking spray and preheat to medium-high.
2. Season both sides of steak with salt and pepper. Place steak on hot pan and cook 3-5 minutes on each side. Note: Steak may also be broiled in the oven on high for 3 minutes on each side for medium-rare.
3. Stuff each lettuce leaf or tortilla with steak, onion, tomato and cheese.