1. Preheat oven to 350ºF/175ºC.
2. Slice the ends the eggplants, then slice them lengthwise into ¼ -inch slices and lay them on a baking tray lined in parchment paper. Season with salt and pepper, drizzle some olive oil. Bake for 15-20 minutes. Let cool.
3. Meanwhile, in a large bowl, mix ricotta cheese, parmesan, mozzarella, egg, lemon zest, nutmeg, salt, pepper and basil.
4. Increase oven heat to 400ºF/200ºC.
5. Spread 3/4 cup (200g) of sauce over bottom of a baking dish. Spoon about 1-2 tablespoons of the mixture onto eggplant slice then roll it up. Arrange the rolls ups in the baking dish, seam-side down. Top with remaining sauce and sprinkle with remaining mozzarella.
6. Bake for about 20 minutes, until cheese is melted and golden brown.