1. Sort and wash beans; place in a large bowl. Cover with water to 2 inches above beans; cover and let stand 8 hours. Drain beans.
2. Place beans, 2 cups water, and next 10 ingredients (through oregano) in an electric slow cooker; stir well. Cover and cook on HIGH for 5 hours or until beans are tender. Stir in vinegar and tomatoes. Serve over rice. Sprinkle with hot sauce, if desired.