Scotch broth is a favorite. Any time I roast a leg of lamb, the leftovers go in a pot with carrot, onion, and a parsnip. Maybe some celery. Sauté it up and add some stock. I usually use chicken or both chicken and beef. Then add barley.
Season with S&P, bay leaf, maybe a little garlic and thyme.
You can really throw about anything in it. I've done it with some lentils added to the barley, added greens (kale or collard) and what ever else strikes your fancy. The lamb, barley, and carrot should be up front though IMO.
