Place the cubed potatoes and chopped onion into the slow cooker insert.
In a small bowl, whisk together the garlic powder, paprika, salt, and pepper.
Pour the spice mixture over the potatoes and onions in the slow cooker.
Drizzle the melted butter over everything and toss gently to coat evenly.
Cover and cook on LOW for 4 hours, or on HIGH for 2 hours, or until potatoes are tender and browned.
Stir occasionally during cooking for more even browning, if desired.
Serve hot.
Notes
These breakfast potatoes are delicious on their own or served alongside bacon, eggs, or sausage. You can also add other vegetables like bell peppers or jalapeños for extra flavor.