Trim steak of fat and pound to 1/4 inch thickness. Place in a plastic bag. Put in lime juice, garlic, and pepper and gently shake. Tie the bag securely and marinate in the refrigerator at least 6 hours, turning the bag over occasionally. Drain steak and place on broiler pan. Broil about 3 minutes per side. carve on diagonal. Arrange on a hot platter. Heat tortillas and spoon in meat with hot sauce or salsa.