Heat the oven to 400°F. Scrub the potatoes clean, prick each one several times with a fork, rub with butter, and sprinkle with salt. Place on a baking sheet and bake for 50 to 60 minutes until the centers are soft when pierced with a knife.
While the potatoes bake, stir the shredded chicken and BBQ sauce together in a mixing bowl until the chicken is evenly coated.
Remove the potatoes from the oven and let them cool for 5 minutes. Slice each potato open lengthwise and fluff the insides gently with a fork.
Spoon the BBQ chicken mixture evenly into the potatoes. Top each one with shredded cheddar cheese.
Return the potatoes to the oven for 8 to 10 minutes until the cheese is melted and bubbly. Serve right away with sour cream and green onions on the side.