Heat the oil in a large Dutch oven or saucepan set over medium heat. Toss in the lamb and cook for 10 minutes, turning occasionally to ensure even searing. Put it on a plate.
Sauté the onion, carrots, and celery in the same saucepan for 5 minutes, or until tender. Add salt and pepper.
Add garlic and tomato paste and cook for 2 minutes, or until the garlic is fragrant and the tomato paste has darkened, before adding cumin, and paprika.
Place the lamb back into the Dutch oven and add the broth, wine, Worcestershire sauce, rosemary, and bay leaves.
Raise the temperature to a boil, then lower to a simmer. Add salt and pepper. Simmer, covered, for 30 minutes, or until the lamb is fork-tender.
Toss in the potatoes and cook them in a covered pot for 30 minutes, or until they’re soft and the stew has thickened.
Take out the bay leaves, and rosemary, and sprinkle on the parsley before serving.