Preheat oven to 375˚F. Place potatoes in a pot, cover with enough water to submerge potatoes. Bring to a boil over medium/high heat then reduce heat to medium and season potatoes will 1 tsp salt. Cook until potatoes are easily pierced with a knife then drain well.

Meanwhile, in a small saucepan, add the butter and milk and cook until butter is melted. Turn the heat off, keep saucepan on the stovetop to keep the milk hot. Add the sour cream and whisk until combined.

Mash or beat potatoes with a mixer until creamy. Add the milk mixture and continue mixing until well incorporated. Transfer potatoes to a baking dish.

In a medium skillet, saute chopped bacon until golden brown. Sprinkle bacon over potatoes and top with shredded cheese.

Cover baking dish with foil and bake at 375˚F for 25 minutes. Remove foil and cook an additional 10 minutes, or until cheese melts and potatoes are hot.