1. Cook bacon in a large Dutch oven over medium heat until crisp. Remove bacon from pan; crumble. Add onion to drippings in pan; sauté 5 minutes or until tender. Add collard greens, and cook 2 to 3 minutes or until greens begin to wilt, stirring occasionally.
2. Place collard green mixture, salt, and next 3 ingredients (through broth) in a 3-quart electric slow cooker. Cover and cook on LOW for 3 1/2 to 4 hours.
3. Combine balsamic vinegar and honey in a small bowl. Stir vinegar mixture into collard greens just before serving. Sprinkle with bacon.