Heat the oil in a large, oven-safe pan over medium-low heat.
Cook the bacon for 4 mins until crisp.
Turn up the heat, then brown the lamb on all sides (for about 6).
Remove the meats with a slotted spoon.
Add the onions, carrots, celery and herbs to the pan, then cook
for about 5 mins until softened.
Add the garlic and cook another minute.
Return the meat to the pan, stir in the pearl barley, pour over the stock, then bring to a simmer.
Place the potatoes on top of the stew, cover, then braise in the oven, undisturbed, for about 1½ hrs until the potatoes are soft and the meat is tender.