Place potatoes in a large pot and cover with salted water; bring to a boil. Reduce heat to medium-low and simmer until tender, about 20 minutes. Transfer potatoes to a bowl of ice-cold water to cool completely.

Place the bacon in a large skillet and cook over medium-high heat, turning occasionally, until crisp, about 10 minutes.; drain on paper towel.

Peel about half of the potatoes; chop peeled and unpeeled potatoes together.

Stir sour cream, sharp Cheddar cheese, scallions, salt, and ground black pepper together in a large bowl; add chopped potatoes and stir to coat.