Put the potatoes on a baking sheet and rub them with the oil. Bake until soft, about 1 hour. Let cool enough so you can handle them.
Slice the butter into pats and add to a large bowl. Add the bacon and sour cream.
Cut each potato in half lengthwise and scrape out the insides into the bowl, being careful not to tear the skins. Leave a small rim of potato intact for support. Lay the hollowed-out skins on a baking sheet.
Smash the potatoes into the butter, bacon and sour cream. Add the cheese, chili powder, green onions and some salt and pepper and mash until smooth. Spoon the filling into the potato skins.
If baking right away, lower the oven temperature to 350 degrees F. Bake until the cheese is melted and the tops are brown, about 15 minutes.
If cooking later, cover the stuffed potato skins with plastic wrap and refrigerate. Bake at 350 degrees F until the cheese is melted and the tops are brown, 15 to 20 minutes.