Best-Ever Lamb Stew

In a large dutch oven or pot over medium-high heat, heat oil. Add lamb and cook on all sides until seared, 10 minutes, working in batches if necessary. Transfer to a plate.  In the same pot, cook onion, carrots, and celery until soft, 5 minutes. Season with salt and pepper. Add garlic, tomato paste, cumin, and paprika and cook until garlic is fragrant and tomato paste has darkened, 2 minutes.  Add lamb back to dutch oven then add broth, wine, Worcestershire sauce, rosemary, and bay leaves.  Bring to a boil then reduce heat to a simmer. Season with salt and pepper. Cover and let simmer until lamb is tender, 30 minutes. Add potatoes and simmer, covered, until potatoes are tender and stew has thickened, 30 minutes.  Remove bay leaves and rosemary and garnish with parsley before serving.