Add the the butter, sour cream, and milk to the potatoes. Beat until smooth. Stir in the garlic, salt, pepper, 3/4 cup of the bacon bits, and half of the cheddar cheese.
1/4 cup unsalted butter, 1/2 cup light sour cream, 1/2 cup skim milk, 1/2 teaspoon kosher salt, 1/8 teaspoon pepper, 1/2 pound bacon, 2 cups shredded cheddar cheese, 1 clove garlic