Cook the bacon in a large Dutch Oven or soup pot over medium heat until crisp and browned. Remove and set aside, leaving some grease for flavor.

Add butter and chopped onion to the pot and cook over medium heat until onions are tender, about 3-4 minutes.

Sprinkle flour, seasonings, and garlic over the onions and stir to form a roux.

Add the diced, peeled potatoes, chicken broth, milk, and heavy cream to the pot. Bring to a boil and cook until potatoes are tender, about 15-18 minutes.

Reduce heat to simmer. Carefully remove a few cups of the potato and soup mixture to a blender and puree until smooth. Alternatively, use an immersion blender to thicken the soup while leaving some potatoes whole for texture.

Let the soup come back to temperature. Serve and garnish with chopped chives, chopped bacon, cheddar cheese, and a dollop of sour cream.