Preheat oven to 450 F.
Pierce potatoes with a fork, and coat lightly with cooking spray.
Bake for 50 minutes or until tender.
Remove potatoes from oven, and cool slightly.
Cut a deep, lengthwise slit in each potato and squeeze the ends to loosen potato flesh.
Combine mayonnaise and next 6 ingredients (through relish) in a medium bowl.
Stir in chicken.
Divide a heaping ½ cup of the chicken mixture among potatoes.
Top each potato with green onions.
