To make the sauce, heat the oil in a saucepan. Add the onions and garlic and fry until the onions are soft.

Stir in the tomatoes, tomato puree (paste) and the remaining ingredients, and bring to the boil.

Reduce the heat to low, cover the pan and simmer the sauce for 30 minutes, or until it is thick and rich. Remove from the heat.

Meanwhile, heat about 50 ml (2 fl oz) (4 tablespoons) of olive oil in a large frying-pan. Add a few of the aubergine (eggplant) slices and fry until they are golden brown on both sides.

Transfer them to a plate. Cook the remaining slices in the same way, adding more oil as necessary.

Preheat the oven to moderate 180°C (Gas Mark 4, 350°F).

Arrange about one-third of the aubergine (eggplant) slices on the bottom of an ovenproof casserole. Cover with half the Mozzarella slices and a third of the sauce. Top with a generous sprinkling of grated cheese. Continue making layers in this way until all the ingredients are used up, finishing with a layer of aubergine (eggplant) slices covered with sauce and grated cheese.

Put the dish into the oven and bake for 45 minutes. Serve at once.