01 - Rub the steak with olive oil, Worcestershire sauce, salt, and pepper in a shallow dish. Let marinate at room temperature for 10 minutes.
02 - Heat a skillet over medium heat. Add butter and sauté the onions and bell peppers (if using) until soft and caramelized, about 8–10 minutes. Transfer to a plate.
03 - Increase skillet heat to high. Sear the steak for 2–3 minutes per side for medium-rare, or until desired doneness is reached.
04 - Rest the steak on a cutting board for 5 minutes, then slice thinly against the grain.
05 - Slice the rolls open and toast lightly.
06 - Mix mayonnaise and Dijon mustard; spread inside the rolls.
07 - Layer arugula, tomato slices, caramelized onions, and bell peppers onto the bottom halves.
08 - Top with sliced steak and cheese. If desired, place under a broiler for 1–2 minutes to melt the cheese. Close sandwiches, slice in half, and serve immediately.