First thing we want to do is to slice the eggplants (0.5cm is the perfect high) and cover each slice with salt, then place it in a strainer with something heavy ontop (for example, a dish and a pot); this will let the eggplant realese all the water, alloweding them to be crispy and boosting the flavor

While eggplants are sitting, cook the tomato sauce (there's the recipe for my tomato sauce too, but you can cook it your own way if you prefer), dice the mozzarella and get all the ingredients ready: put the flour in a dish and in a large bowl beat the eggs (remember to add salt here); get ready with an empty dish too, you will need it

In 10 minutes your eggplants should be ready, so rinse them and wipe them with a towel; now, it is going to be like a puzzle: flour each slice, then put in the eggs and then again in the flour; do it for all of them and let it sit in empty dish prepared

Now you have three ways you can cook them: deep-frying is the most traditional one (but takes a long time), air-frying (160°C- 320°C, 15 mins flipping them after 8 mins and spaying with oil up and bottom) or my favourite one, place them on sheetpan with parchment paper on, spray some oil and cook in the oven, fan-assisted 16 mins 180°C - 350°F, flipping them at 8 mins

Once they are ready, most of your job is done: now you just have to "built it" as you would do with a lasagna: take a casserole and layer eggplant, tomato sauce, mozzarella, Parmesan cheese and basil, cover evenly and start with the next layer; the perfect number of layers is 3 or 4, but you can do less if you want it crispier or more if you prefer it creamier

Bake it fan-assisted 25 mins 180°C - 350°F (that's why I love cooking the eggplants in the oven too, so it will be pre-heat for the parmigiana). When it is brown, crispy and you see the tomato sauce not "bubbleing" anymore, it is ready!