Mix all the ingredients in a bowl, and then add the lamb shanks. Leave in the fridge for a minimum 12 hours or preferably over night, as this helps to flavour and tenderize the meat.
Place the marinated lamb shanks in an oven tray. Pour ½ pint of cold water in the bottom of the tray. Cover the tray with foil, and place in a preheated oven 160ºC/320ºF/Gas mark 3 for 2½-3 hours. Remove the foil for the last hour to add the vegetables.
Check every hour to insure it is not dried out and if it is, add a little more water. The lamb should be tender and ready to fall of the bone.
While the lamb is cooking, prepare the roasted root vegetables. Tumble all the ingredients in a large bowl. Place the vegetables in the roasted trays with the lamb for the last hour until cooked.
Remove cooked Lamb shanks and vegetables from the tray and place on a plate, cover and leave to rest in the warm oven.
Place roasting tray over a low heat and add the lamb stock, red currant jelly and crushed garlic. Reduce by ½ and strain into a clean pan and season to taste.
Evenly place the roasted vegetable in the centre of each plate. Place each lamb shank on top of the vegetables a carefully pour the finished sauce over the lamb.
For top tips on protecting you and your family when preparing raw meat and poultry, visit Food Safety in the Home and view the full Food safety at home video.