Got a 1.2kg leg of lamb - what's the best option for slow cooking? (No working oven at the moment)

Question is the question is the question. I've got this huge leg of lamb sitting in my freezer, and I've no clue what to do with it. I don't have a working oven at the moment, so my slow cooker is the best option right now. What's the best (and cheapest) way to prepare this big fucker?