Preheat oven to 350 degrees.
Stab each potato with a fork 4-5 times and bake in preheated oven for 1 hour.
Meanwhile, place bacon in a large, deep skillet. Cook over medium high heat until evenly brown. Drain, crumble and set aside.
When potatoes are done allow them to cool for 10 minutes. Slice potatoes in half lengthwise and scoop the flesh into a large bowl; save skins.
To the potato flesh add sour cream, milk, butter, salt, pepper, 1/2 cup cheese, bacon and chives.
Mix with a hand mixer until well blended and creamy.
Spoon the mixture into the potato skins.
Top each with remaining cheese and return to the oven to bake for another 15 minutes.
Top with extra bacon and more chives.