Preheat the oven to 180°C/350F/. Cut the tops off the eggplant/aubergine then cut into slices around 1cm / 1/4 inch thick. Place on a lined baking tray, brush with a little olive oil (2 tbsp) and bake for 20 minutes until tender. Set aside to cool.
Meanwhile add half tbsp of olive oil to a frying pan and add the spinach, stir so it doesn’t burn until completely wilted. Remove from the pan and let cool.
To make the tomato sauce, add a tbsp of olive oil to the frying pan. Add the finely chopped shallot and garlic to the pan.
Sauté for 1 minute then add the chopped tomatoes. Rinse out any excess tomato from the can with 1/4 cup (60ml) water and add it to the sauce alongside the tomato paste, oregano and season with salt and pepper. Let the sauce reduce and simmer for 15 minutes.
Squeeze out any extra moisture from the wilted spinach then finely chop and add to a large bowl. Add the ricotta, parmesan, nutmeg and a pinch of salt and pepper. Mix everything together until thoroughly combined.
To assemble the eggplant roll-ups, add a spoonful of ricotta mixture (about a heaped tbsp) in the centre of a slice of eggplant then roll it up. Repeat with the rest of the eggplant and ricotta mixture.
Add 3/4 of the tomato sauce to the bottom of a baking dish. Arrange the eggplant roll-ups in the baking dish then top with the remaining sauce. Top with mozzarella then bake in the oven for 20-25 minutes until the mozzarella is golden and melted and everything is heated right through.