Cut the eggplants into 1 cm thick circles. Fry the eggplant in flour on both sides in olive oil until golden brown.
Cut the mozzarella into small cubes. Grate parmesan.
Put the tomatoes in their own juice in a saucepan, add salt, sugar, 2 tablespoons of olive oil and a generous pinch of dry basil. Cook about 1/3 over low heat. Then grind smooth with a blender.
Put the eggplant circles into the towers (5-6 pieces each). Spread tomato paste on each layer and spread the mozzarella cubes. Sprinkle parmesan on the top of the towers.
Bake in an oven preheated to 180 degrees for 7-10 minutes.