Preheat the oven to 180°C (350°F). Slice the tops off the eggplants and cut them into 1 cm (¼ inch) thick slices. Arrange the slices on a lined baking tray, brush with 2 tablespoons of olive oil, and bake for 20 minutes, or until tender. Set aside to cool.

Meanwhile, heat ½ tablespoon of olive oil in a frying pan over medium heat. Add the spinach and cook, stirring occasionally, until completely wilted. Remove from heat and let cool.

For the tomato sauce, add 1 tablespoon of olive oil to the pan. Sauté the finely chopped shallot and garlic for 1 minute. Add the canned chopped tomatoes and rinse the can with ¼ cup (60 ml) water, adding it to the pan. Stir in the tomato paste, oregano, and season with salt and pepper. Let the sauce simmer and reduce for 15 minutes.

Squeeze out any excess moisture from the cooled spinach, then finely chop it and combine with ricotta, parmesan, nutmeg, and a pinch of salt and pepper in a large bowl. Mix until well combined.

To assemble, place a spoonful of the ricotta mixture (about a heaping tablespoon) in the center of each eggplant slice and roll it up. Repeat with the remaining eggplant slices and ricotta mixture.

Spread ¾ of the tomato sauce on the bottom of a baking dish. Arrange the eggplant roll-ups in the dish and top with the remaining tomato sauce. Tear the mozzarella ball and scatter over the top. Bake in the oven for 20-25 minutes, or until the mozzarella is golden and melted and the dish is heated through.