Preheat the oven to 400°F (200°C) mark 6. Oil two shallow baking sheets or trays.

Cut off both ends of the aubergines, rinse and dry. Cut into round, even slices about 1/4 in (7 mm) thick. Place these on the oiled trays, brush the exposed cut surfaces with olive oil and season with salt and freshly ground pepper.

Bake in the oven for 6 minutes.

Chop the tomatoes and drain off excess liquid. Take the trays of aubergine slices out of the oven and place a few pieces of tomato on top, sprinkle with a small pinch each of salt, pepper and dried oregano, some Parmesan and a tiny piece of butter and cover with a slice of mozzarella cheese.

The 'pizzas' can be prepared up to this point a few hours in advance if wished.

Return to the oven for 15 minutes, then serve piping hot while the mozzarella cheese is still very soft.