Preheat the oven to 200°C/Gas 6. Score the flesh of both halves of aubergine and drizzle with half the oil. Heat the remaining oil in a frying pan and cook the onions and garlic until softened, set aside. Place the aubergine halves onto a baking sheet and season well with salt and freshly ground black pepper. Transfer to the oven and roast for 20 minutes or until the flesh is soft. Scoop the cooked flesh out of the aubergines and combine with all the other ingredients except the Parmesan cheese. Place the mixture back into the aubergine halves and sprinkle over the parmesan cheese and place back in the oven for 15 – 20 minutes until heated through and golden-brown.
To serve, place the stuffed aubergine halves onto two plates.