In a large, heavy-bottomed pot over medium-high heat, cook bacon until golden brown. Remove cooked bacon to a paper towel-lined plate and reserve.
Add leeks and garlic to the bacon fat and cook until tender, about 4-5 minutes. Add in the thyme, paprika, some salt and freshly ground black pepper. Add potatoes and stock to the pot and bring up to a bubble. Reduce heat to medium and simmer the potatoes until cooked through, about 8-10 minutes. When the potatoes are tender, puree the soup until smooth using a blender, food processor or immersion blender.
Adjust the seasoning as needed with salt, freshly ground black pepper and hot sauce, if desired. Serve the soup in a bowl or mug topped with some of the two cheeses, reserved bacon, a sprinkling of scallions, a dollop of sour cream and a dash of paprika.