Place the lamb in a saucepan and completely cover with the stock. Simmer gently for two hours or until the meat is tender. Top the pan up with water if necessary to ensure the meat remains covered. Skim as required.
Remove the meat from the stock and pull into chunks when cool enough to handle.
In a clean pan, heat a little oil and gently cook the vegetables until soft.
Add the peas, barley and stock.
Add the meat, simmer gently for 30 minutes and adjust the seasoning.
Serve in large bowls, garnished with chopped parsley and with a side of crusty bread.