This is such an easy entertaining dish, where the lamb is wrapped in foil with vegetables and slow roasted to perfection, then served with a rich redcurrant sauce.
Peel the onions and carrots. Cut the onion in half and slice lengthways and slice the carrots at an angle. Lay out 2 large squares of foil and divide the vegetables.
Peel the garlic and cut each clove into 4 or 5 slithers. Make deep cuts on both sides of the lamb shanks and stuff each cut with a piece of rosemary from 1 sprig and a piece of garlic.
Season the lamb all over with the salt and pepper.
Put the oil in a frying pan over a medium to high heat. Sear the lamb all over, turning so that all areas are browned.
Divide the remaining rosemary between the vegetables and place the lamb shank on top. Bring two opposite corners together and fold the foil to seal, then fold up the other ends.
Preheat the oven to 160 C / 310 F / 140 FAN / Gas 2.5. Cook for 2 to 2.5 hours until tender. Let the lamb rest in a warm place.
Make the sauce by deglazing the frying pan with the wine. Scrape off any residue with the wooden spoon then add the redcurrant jelly and stock, (or juices from the lamb). Bring to a boil and check the seasoning.