Salt and pepper the two steaks. Heat oil in the skillet under medium high heat and cook the steaks for about 3-4 minutes per side. Lower heat to medium, transfer the steaks to a separate plate and cover with aluminum foil. Add the onion and pepper strips to the skillet and cook, stirring until the vegetables are soft and wilting, about 10-12 minutes. Stir in the dash of cayenne and vinegar and cook another minute. Add the juices that have accumulated around the steaks to the skillet and spoon the vegetables onto the toasted rolls on your plates. Top each roll with the steaks and spoon any juices in the pan over all. Now you have a great steak sandwich!