Preheat the oven to 400 degrees. Place the potatoes on a baking sheet and drizzle vegetable oil over top then rub the oil over each potato coating it. Bake the potatoes uncovered in the oven for about 40 minutes or until they can be sliced easily.

Measure out the butter, sour cream and milk and set out so they come to room temperature.

While the potatoes are baking, cook the bacon in a large skillet over medium high heat. You want the bacon to be cooked but not crisp. Transfer to a paper towel lined plate and crumble when cool.

After the potatoes are done baking, lower the oven temperature to 350 degrees.  Allow the potatoes to cool enough to handle. Peel all but 2-3 potatoes. Cut each potato in thirds and place in a large bowl.

Add the butter, sour cream, milk, season salt, salt and pepper. Using a potato masher, mash the potatoes together until everything is combined and creamy.

Add the crumbled bacon and shredded cheese. Be sure to leave a bit of bacon and cheese for the topping of the casserole. Mix again until everything is combined.

Spray a 9×13 baking dish with nonstick spray and add the potato mixture to the dish. Spread out evenly. Top with the remaining bacon and cheese.

Bake uncovered at 350 for 25 minutes. Remove from the oven, top with chopped green onions and serve!