Place the lime juice, cumin, garlic, cayenne, salt and pepper into a plastic zip bag. Place the chicken in it and zip it, making sure all of the chicken strips are well coated. Let it stand for about 20 minutes or place it in the fridge for up to 2 hours.
Heat a large oiled skillet over medium-high heat (see tips below). Add the chicken and stir-fry it until it is lightly browned and the marinade has thickened slightly into a sauce. Remove the chicken. Saute the peppers and onion until they are tender crisp. Return the chicken to the pan. Toss it with the peppers and onions. Sprinkle the chopped cilantro on top.
Wrap the chicken and vegetable mixture in flour tortillas. Serve with plenty of grated cheese, sour cream, lettuce, hot sauce, guacamole and salsa.