Pre-heat the oven to 180°C / gas mark 4.
Sprinkle salt on the eggplant slices, leave for 20 minutes and pat dry with paper towels.
In a separate bowl, mix the ricotta, egg and fresh parsley and season to taste.
Pour the oil into an oven-proof pan and bring to a medium heat.
Cook the shallots until softened and translucent.
Add the garlic and stir well, ensuring it doesn’t burn.
Pour in the marinara sauce, add the oregano and simmer gently for five minutes.
Ladle a thin layer of cooked marinara sauce onto the bottom of an ovenproof casserole dish.
Arrange a layer of eggplant slices on top, then another layer of ricotta mixture and then a layer of mozzarella.
Repeat twice and add a sprinkle of Parmesan on top of the final layer.
Cover the dish with foil and bake it in the oven for 35 minutes. If you like your cheese extra-crunchy, remove the foil and place under the grill for five minutes for that perfect golden finish.
Garnish with freshly-chopped parsley.