How to Make It
Place the potatoes in a large pot and add 2 teaspoons salt and enough cold water to cover. Bring to a boil. Reduce heat and simmer until the potatoes are very tender, 20 to 25 minutes. Drain and return the potatoes to the pot.
Meanwhile, in a large skillet, cook the bacon over medium heat until crisp, 5 to 8 minutes. Transfer to a paper towel-lined plate. Let cool, then crumble.
Add the milk, butter, ½ teaspoon salt, and ¼ teaspoon pepper to the potatoes and mash to the desired consistency. Fold in the bacon and top with the blue cheese.