Preparation Steps

• Using a fork or paring knife, prick skin of potatoes all over. Working in batches if needed, place potatoes on microwave-safe plate and microwave on high power, flipping halfway through, until potatoes can be easily pierced with a paring knife, 12 to 14 minutes. Let potatoes sit until cool enough to handle. Peel the potatoes and pass through a ricer into a medium bowl; set aside.
• While potatoes cook: In a 6-quart pot, cook bacon over medium heat, stirring constantly, until bacon is crisp and fat is rendered, about 12 minutes. Using a slotted spoon, transfer bacon to a paper-towel lined plate to drain. Pour off all but 3 tablespoons bacon fat from pot.
• Add onion and garlic to remaining bacon fat in pot and sauté over medium heat until very soft but not browned, 8 to 10 minutes. Add milk, season with salt and pepper to taste. Bring to a boil over high heat, reduce to a gentle simmer and cook until flavors meld, about 10 minutes.
• Using an immersion blender, purée onion, garlic, and milk until smooth. Add riced potatoes and sour cream, stirring to combine, until soup is warmed through. Season to taste with salt and pepper, and serve. Garnish with sour cream, chives, cheddar, and potato chips, if desired.