Cut the chicken breast into bite-sized pieces.
Slice the onion and bell pepper into thin strips.
Heat olive oil in a pan and stir-fry the chicken breast.
Once the chicken is cooked, add the onion and bell pepper, and stir-fry together.
Place cheese on top of the tortilla, then add the stir-fried ingredients.
Fold the tortilla in half and cook in the pan until golden brown.
Slice the finished tortilla into easy-to-eat pieces.