Brown off lamb joint in a pan.
Pierce the joint in several places.
Crush garlic and rub over joint.
Stuff rosemary sprigs in pierce holes.
Place joint in slow cooker.
In a jug...
With boiling water, make up the lamb stock and mix in the redcurrant jelly, mint sauce, mixed herbs and red wine
Add baby carrots and green beans if using.
Pour liquid over lamb and put on LOW for 6-8hours
Remove lamb and veg (if used) and set aside on a plate, cover with foil to keep warm.
Pour liquid into a pan, place over a high heat and thicken with cornflour, stirring constantly.
Serve with mashed potato.