Preheat the oven to moderate 180°C (Gas Mark 4, 350°F). Cut the aubergines (eggplants) in half, lengthways, and make two or three slits in the flesh. Place the halves, flesh side up, in a baking dish. Cover with foil and put the dish into the oven. Bake for 1 hour, or until they are soft. Remove from the oven and set aside to cool.

When the aubergines (eggplants) are cool enough to handle, scoop the pulp from the skins and transfer to a bowl. Discard the skins. Mash the pulp to a smooth puree, then beat in the tomatoes, coriander, cumin, turmeric and 1 tablespoon of the coriander leaves. Set aside.

Heat the ghee or oil in a large frying-pan. Add the onion and fry until it is soft. Stir in the garlic, ginger and chilli and fry for 5 minutes, stirring frequently. Stir in the aubergine (eggplant) mixture and salt and cook, stirring frequently, until the liquid has evaporated and the mixture is thick and smooth.

Transfer the bharta to a warmed serving dish, sprinkle over the lemon juice and remaining coriander leaves, and serve at once.