Heat your oven to 200°C/Fan 180°C/Gas 6. Rinse and trim the aubergines. Slice in half lengthways. Use a knife to slice diagonal lines across the surface of the flesh. Place, cut side up, in an ovenproof dish.
Brush the aubergines with ½ tbsp olive oil. Season with salt and pepper. Bake for 20 mins or till the flesh is tender. Remove from the oven and leave till cool enough to handle. Peel and chop the onion. Peel and crush the garlic.
Heat a frying pan with a ½ tbsp of oil. Add the lamb mince and cook over a medium heat for 4 mins. Add the garlic and onion. Fry for another 3 mins. Strip the oregano leaves from the stems. Rinse them and pat dry. Roughly chop them.
Stir 1 tsp cinnamon into the mince and cook for 30 secs. Add the chopped tomatoes. Half fill the can with water and add to the pan with a little seasoning and the oregano. Stir well.
Bring to the boil. Stir. Lower the heat and simmer, uncovered, for 10 mins till thickened and reduced. When the aubergines have cooled slightly, use a spoon to scoop out the flesh, leaving their skins intact.
Roughly chop the aubergine flesh and add to the mince. Stir to mix. Spoon the mince mix back into the aubergine shells and pop back in the ovenproof dish. Crumble half the pack of feta over the top.
Bake at the top of the oven for 20 mins. Rinse the salad leaves. Dry in a salad spinner or pat dry with kitchen paper. Pop into a bowl. In a small jug whisk 1 tbsp of the vinegar together with 1/2 tbsp of olive oil and some salt and pepper.
Divide the aubergines between two warmed plates. Drizzle the dressing over the leaves and toss to mix. Serve alongside the aubergine.