Place the aubergines cut-side up on a baking sheet and brush each with a little of the oil. Cook in a preheated oven, 200°C (400°F), Gas Mark 6, for 30–35 minutes until the flesh is tender, then remove (leaving the oven on) and leave to cool. When the aubergines are cool enough to touch, scoop out the flesh and roughly chop. Reserve the skins.
Meanwhile, place the couscous in a heatproof container, pour on the measurement water and cover with clingfilm. Set aside for 5 minutes, then remove the clingfilm and fork through.
Heat the remaining oil in a nonstick frying pan, add the onion and garlic and fry for 3 minutes, then stir through the apricots, raisins, lemon rind and juice, couscous, herbs, Parmesan and aubergine flesh.
Spoon this mixture into the aubergine skins and return them to the oven for 10 minutes.
Mix together the tzatziki ingredients in a serving bowl and serve with the aubergines and flat breads.