Place plain flour and lamb in a snap-lock bag. Shake to coat. Heat oil in a saucepan over medium-high heat. Cook lamb, in batches, for 3 to 4 minutes or until browned. Transfer to a 4.5 litre-capacity slow cooker.
Add Gourmet Garden Chunky Garlic, Gourmet Garden Rosemary and onions to saucepan. Cook, stirring, for 4 to 5 minutes or until onion is tender.
Add beef stock and water. Bring to the boil. Transfer mixture to slow cooker. Add carrots, celery stalks and pearl barley to slow cooker. Stir to combine.
Cook, covered, on LOW for 5 hours or until lamb is tender. Add zucchini. Cook on LOW for a further 30 minutes. Stir in Gourmet Garden Parsley