Scrub potatoes; prick with a fork. Wrap each in foil and bake in a 350 degree oven for 1 1/2 hours or till done. Remove potatoes.
Increase oven temperature to 425 degrees.
Cut each potato in half lengthwise. Scoop out the insides of each half and place into a medium bowl; mash. Add butter. Beat in enough milk to make of stiff consistency. Season to taste with salt.
Pile mashed potato mixture into potato halves. Sprinkle each half with shredded cheese and bacon. Place in a 10x6x2-inch baking dish. Bake in a 425 degree oven for 20 to 25 minutes or until cheese is melted.