Clean the aubergines and cut them lengthways into approx. 1 cm thin slices using the slicer. Sprinkle the slices lightly with salt and let stand for about 20 minutes (draw in water). Then pat the aubergine slices dry with kitchen paper. Brown the slices in olive oil on both sides. Then cover the aubergines with a thin slice of Parma ham, a piece of mozzarella and a basil leaf, roll up tightly and pin in place with a toothpick.
Blanch the tomatoes, remove the skin and finely dice. Peel and dice the onion and fry well in the oil for 15 minutes, add the tomato cubes and let everything simmer over a medium heat for about 30 minutes.
Season the tomato sauce with tomato paste, sugar, salt and freshly ground pepper. Put the sauce in a baking dish and place the eggplant rolls on top. Garnish with basil. The typical Italian dish can be eaten either lukewarm or cold. It can also be briefly reheated in the oven and served with pasta.