Slice the eggplant into thin slices, about 1-2 mm thin. Lay out slices on a baking tray lined with baking paper. Sprinkle some salt all over the slices.
Add about 1-2 tablespoons tomato sauce on each slice and spread to cover the whole surface - I left 1 mm from the edges.
Top with diced mozzarella, again trying to cover the whole surface and not only in the middle. Bake in the preheated oven at 200°C for 20 minutes, or until the eggplant skin feels soft and easy to break and the cheese has melted and browned some.
Notes
Baking time may vary depending on eggplant type and thickness of slices. As a general rule, you know the eggplants are done when the skin feels soft and easy to tear and the flesh gives very easily when pierced. If after 20 minutes your eggplant still feels firm when pricking with a fork, bake longer and check again after 5 minutes. I prefer to use mozzarella balls, that I cut into a fine dice. The higher moisture of fresh mozzarella, as opposed to the drier compact one that is generally preferred for pizza, makes for better results in the eggplant. For a great homemade tomato sauce from scratch that only requires 4 ingredients and no sugar check out my best pizza sauce recipe.Please notice that the nutritional information provided at the bottom of this recipe card is only meant as a guideline.