Scrub the potatoes; pat dry and wrap in aluminum foil. Bake at 400°F for 1 hour or until done.
Cook the pepper and the onion in the butter in medium saucepan until tender; add the taco seasoning mix and cook for 1 minute, stirring constantly. Remove from the heat; stir in the chicken, cheese, olives, and chilies.
Cut a lengthwise slit in the top of each potato; press each potato open and spoon the chicken mixture into the potatoes. spoon 1/4 cup of salsa over each potato.
Serve with sour cream, guacamole, and additional salsa.