For the potato-melanzani casserole, crush the tomatoes with the help of a fork. Peel the garlic cloves and chop finely.
Wash the parsley and basil, spin dry, pluck the leaves and chop finely. Peel onion, wash, finely dice and fry in sunflower oil.
Add the garlic and fry for 1 minute. Add the tomatoes and stir. Turn heat down low and simmer without lid for 10 minutes until sauce is thickened and reduced slightly, stirring occasionally.
Stir in the parsley and basil and season the sauce with sea salt, pepper, sugar and a pinch of cinnamon. Brush a baking dish with butter. Peel the boiled potatoes.
Wash the melanzani, pat dry, cut off the stem and cut both into thin slices. In a baking dish greased with butter, layer potato slices alternating with melanzani slices in a roof-tile fashion.
Season with sea salt and pepper. Spread the tomato sauce on top and sprinkle with grated cheese. Bake the potato-melanzani casserole in a preheated oven at 180 degrees,about 30 minutes, until golden brown.
Spread the casserole on warmed plates, sprinkle with finely chopped parsley and serve immediately.