When potatoes are done allow them to cool for 10 minutes. Slice potatoes in half lenthwise adn scoop the flesh into a large bowl; save skins. To the potato flesh add sour cream, milk, butter, salt, pepper, 1/2 cup cheese and 1/2 the green onions. Mix with a hand mixer until well blended and creamy. Spoon the mixture into the potato skins. Top each with remaining cheese, green onions and bacon.