Brown the lamb in olive oil in batches so that all the meat is coloured and starting to brown a little at the edges. It's important to do this in batches so that you don't stew the lamb
Fry the onion and garlic in the fat till soft and browning at the edges
Finally fry the aubergine chunks to seal all sides
Put the lamb, onion, garlic, aubergine, olives, tinned tomatoes, wine, rosemary, chilli and cinnamon into a large casserole and bring to the boil on the top of the stove
Once the mix is simmering gently transfer to an oven at 140-150c and cook for at least 1hour 30 minutes, stirring and adding more water as necessary
Once cooked, check the mix for 'heat' and remove the chilli and cinnamon stick if used. Add pepper if necessary. Do NOT add salt at this stage because the feta is quite salty.
Plate up and add crumbled feta and mint to taste. I've served this with tagliatelli, but it works very well just with a big chunk of crusty bread.