How to Make It
Place sweet potatoes, sugar, butter, salt, cinnamon, and vanilla in a 6-quart slow cooker coated with cooking spray; stir together to coat. Cover and cook until potatoes are tender, 2 hours, 45 minutes to 3 hours on HIGH or 6 to 7 hours on LOW. Sprinkle with marshmallows; cover and cook on HIGH until marshmallows are soft, about 15 minutes. Sprinkle with pecans.