Wash and scrub the baking potatoes thoroughly. Pat them dry and prick them with a fork a few times to allow steam to escape during baking.
Rub with oil and sprinkle with salt. Place them directly on a baking sheet. Bake for about 45-60 minutes, or until they’re tender when pierced with a fork.
Fry the bacon in a skillet over medium heat until crispy. Drain on paper towels and then chop or crumble. Set aside.
Remove the potatoes from the oven and let them cool slightly so you can handle them. Cut each in half lengthwise. Carefully scoop out the insides, leaving a thin shell to hold the filling.
In a mixing bowl, mash the potato insides with a fork or potato masher. Add the sour cream, milk, butter, half of the crumbled bacon, half of the shredded cheddar, half of the chopped scallions, salt, and pepper. Mix well until the ingredients are combined and the mixture is creamy.
Spoon the mixture back into the shells, mounding it slightly. Top each with the remaining shredded cheddar and crumbled bacon.
Place the pan back in the oven and bake for an additional 15-20 minutes, or until the cheese is melted and bubbly.
Remove the pan from the oven and sprinkle with the remaining chopped scallions. Let the potatoes cool for a few minutes before serving.