Preheat the oven to 400 F. Wash the potato, then coat it in the oil. Place on a small rimmed baking sheet, and bake for one hour.*
Line a separate small rimmed baking sheet with foil. Lay the bacon strips onto the foil, leaving space between them. Pop the bacon into the oven when the potatoes have about 15 minutes remaining, and cook it at 400 F for 15-18 minutes until browned and crispy.
After an hour of baking, remove the potato from the oven and gently pierce it with a knife to make sure it is completely cooked through and tender. Carefully transfer the baked potato to a cutting board, and turn the oven down to 350 F. Allow the potato to cool for a few minutes before handling.
Transfer the cooked bacon to a plate lined with paper towels, and allow it to cool. Chop it into small pieces once it's cool enough to handle.
Cut the butter into small cubes, and place the cubes into a large bowl.
Cut the potato in half lengthwise.
Carefully scoop out the insides of the potatoes, leaving the skins intact. (It helps to leave about 1/2" of potato around the edges so they don't tear apart.) Place the scooped out potato directly into the bowl with the butter. Sprinkle with sea salt and black pepper, and mix to combine until the butter is melted.
Stir in the green onions and sour cream.
Stir in the cheese, chopped bacon, and whole milk. Taste, and season with more salt or pepper if desired.
Divide the potato mixture between the hollowed potato halves, then pop them back in the oven. Bake at 350 F for about 10 minutes until hot. Enjoy!