Heat the oven to 425°F. Pierce each potato several times with a fork, rub lightly with oil, and season with salt. Bake directly on a sheet pan for 50 to 60 minutes, until the centers are soft.
While the potatoes bake, combine the shredded chicken, buffalo sauce, melted butter, and a pinch of black pepper in a small pan. Warm gently for 5 to 7 minutes, stirring until the chicken is coated.
Split each hot potato down the middle and fluff the inside with a fork. Add a small pinch of salt and spoon the buffalo chicken evenly into the potatoes.
Top each potato with cheddar cheese and return the tray to the oven for 3 to 5 minutes, just until the cheese melts. Drizzle with ranch and finish with green onions.
