Rub 2 tablespoons of the oil over the aubergine slices and season well. Heat a griddle pan until smoking hot, then cook the aubergine for about 5 minutes until soft and lightly charred all over.
Mix the spices, garlic, lemon rind and juice and coriander with 3 tablespoons of the oil, season to taste and toss with the tomatoes and warm aubergine.
Rub the remaining oil over the lamb and season to taste. Cook in the griddle pan for 3–5 minutes on each side until golden on the outside and still just pink in the middle. Serve with the tomato and aubergine salad.