Place the potatoes, cauliflower, onion, celery, garlic, one of the scallions, paprika, thyme, salt and pepper into your slow cooker and stir together. Pour in the broth. Cook on high for 4 hours or on low for 8 hours until the vegetables are tender.

Using an immersion blender, blend the ingredients until smooth (if you don’t have an immersion blender, you can transfer the soup in batches into a regular blender until smooth and then return to the slow cooker pot). Add the half and half and sour cream and stir until thoroughly combined.

Top each serving with ½ ounce of shredded cheddar, a slice of the crumbled bacon, and some of the remaining sliced scallions.