Step 1

Combine lamb with juice and half of the garlic in large bowl. Cover, refrigerate 3 hours or overnight, turning lamb occasionally in marinade.

Step 2

Preheat oven to 180°C (160°C fan-forced).

Step 3

Cut each potato into eight wedges. Place undrained lamb and potatoes in large flameproof baking dish, roast, uncovered, 1 hour.

Step 4

Combine ingredients for gremolata in small bowl, press onto lamb. Roast, uncovered, further 30 minutes or until lamb is cooked as desired.

Step 5

Remove lamb and potato from baking dish. Cover, keep warm.

Step 6

Cook onion, celery and remaining garlic in baking dish, stirring, over heat until vegetables are soft. Stir in flour, cook, stirring, about 1 minute or until bubbling. Gradually stir in wine and stock, add rosemary, cook, stirring, until gravy thickens. Strain gravy into medium jug.

Step 7

Serve lamb and potato wedges with gravy; sprinkle with parsley.