In a medium kettle, add the lamb, boiling water, bay leaf, pepper, and salt, and bring all of this to a boil. Turn your heat down, cover, and let it simmer for about 1 hour.
Then you need to add the carrot, onion, celery, and the potato. Next, bring this to a boil, turn your heat down yet again, cover, and let this simmer for about 25 minutes or till your lamb and veggies are tender. Once they are tender you can now remove the bay leaf.
In a small bowl, mix together the flour and ¼ cup of the water and continue to mix till you have a really smooth paste. No lumps, please!
Once you have a smooth paste you can stir this mixture into the hot stew, and then add your parsley. Bring this back to a boil. Make sure to continuously stir the stew and let it continue to boil until the stew has thickened up.