01 -
Heat olive oil or butter in a skillet over medium heat. Add the sliced chicken breast and season with salt, pepper, and optional garlic powder. Cook, stirring occasionally, until fully cooked and golden, about 6–8 minutes. Transfer the chicken to a plate and keep warm.
02 -
In the same skillet, add the sliced green bell pepper and onion. Cook over medium heat, stirring occasionally, until softened and lightly caramelized, about 5–7 minutes.
03 -
Return the cooked chicken to the skillet with the vegetables. Stir to incorporate and heat through for 1–2 minutes.
04 -
Spread mayonnaise evenly on the inside of each hoagie roll.
05 -
Divide the chicken and vegetable mixture between the hoagie rolls. Place 2 slices of Swiss cheese on each sandwich.
06 -
Arrange the filled rolls open-faced on a baking tray and place under a broiler for 1–2 minutes, or until the cheese is fully melted.
07 -
Serve the sandwiches hot, ideally on a white plate for best presentation.