Heat oven to 190C/fan 170C/gas 5. Leaving the stem on, cut the aubergine in half lengthways and score the flesh deeply with a sharp knife in a criss-cross fashion. Place in a shallow baking dish. Mix the olive oil and lemon juice then brush over the scored surface of the aubergine. Season with freshly ground black pepper and bake uncovered for 25-30 mins, until the flesh is tender.
Meanwhile, put the couscous in a large bowl, pour over the boiling stock and leave to soak for 10 mins until all the stock is absorbed. Fluff up with a fork, then stir the apricots, tomatoes, spring onions and pine nuts into the couscous. Sprinkle with the cinnamon and toss well together.
Remove the aubergine from the oven and scoop out the flesh, taking care to keep the skins intact. Chop the flesh and toss into the couscous mixture. Place the aubergine skins back in the baking dish and spoon the couscous mix into them, piling it up to hold a generous amount in each. Scatter any left over couscous mix around the edge of the dish.
Return to the oven for 10 mins to heat through while you mix all the dressing ingredients together - add a drop of water if the dressing is too thick. To serve, heap the loose couscous mix under the stuffed aubergines so they're propped up on a slant. Drizzle over dressing and serve with mixed leaf salad.