Preheat your oven to 350°F.

Scrub the potatoes and dry them thoroughly. Then, prick them several times with a knife or a fork.

Place the potatoes on a rimmed baking sheet and bake for 90 minutes. They are done when a fork can easily pierce the center of them—it should slide in with little to no resistance—the internal temperature should be between 200 and 210°F, as measured with a meat thermometer.

While the potatoes are cooking, place the butter, sour cream, heavy cream, salt and pepper, and one tablespoon of chives in a large bowl and allow everything to come to room temperature.

When the potatoes are done and cool enough to handle, but while they are still hot, cut them in half with a sharp knife, scoop out the insides, and add them to the bowl with the other ingredients.

Use a potato masher to mash the potato mixture until it is fairly smooth and everything is well combined. A few small chunks are fine. If the mixture looks too dry, add a tablespoon or so more of heavy cream. Add one cup of the cheese, most of the crumbled bacon, and one tablespoon of the chives and stir to combine.

Spray a small casserole dish with nonstick cooking spray and add the potato mixture. Smooth out the top and sprinkle the remaining shredded cheese, bacon, and chives evenly over it.

Place the dish in a 350°F oven and bake the potato casserole for 30 minutes or until it is heated through and the cheese has melted.