Cut the chicken breast into bite-sized pieces.
Slice the onion and bell pepper into thin strips.
Season the chicken breast with salt and pepper.
Heat olive oil in a pan and cook the chicken breast.
Add the onion and bell pepper to the chicken and stir-fry.
Place the cooked ingredients, shredded lettuce, and sliced cheese on a tortilla.
Drizzle mayonnaise or your preferred sauce.
Roll the tortilla tightly to form a wrap.