Sprinkle the ribs with salt and pepper. Heat a large skillet set medium-high heat, I like using cast iron. Add the ribs and cook, turning once, until browned, about 8 minutes.
Transfer the ribs to a slow cooker. Add the onions, potatoes, carrots, garlic, and bay leaf. Pour the broth and Worcestershire sauce over the meat and vegetables. Cover and cook until the meat and vegetables are fork-tender, 4–5 hours on high or 8–10 hours on low.
About 20 minutes before the cooking time is up, make the slurry. Combine the flour and water in a small bowl until smooth; stir in about 1⁄4 cup of the hot liquid from the slow cooker until blended. Stir the flour mixture into the slow cooker. Cover and cook on high, until the mixture simmers and thickens, about 15 minutes. Discard the bay leaf. Stir in the parsley just before serving.
Notes
Cooking Time - 4 - 5 hours on high; 8 - 10 hours on low