Add the potatoes and broth to a smaller about 4.5-quart slow cooker. Cook on HIGH for 3 hours until the potato is quite tender.
Stir in the sour cream and melted butter. Salt and black pepper, to taste. If using salted butter, you may not need any extra salt.
With a potato masher (recommended for chunky texture) or an immersion blender (recommended for silky smooth texture) blend the potatoes until desired consistency.
These can be a little chunky or smooth depending on your preference. Serve with sliced scallions on top. Enjoy!