Switch on the oven with grill function for preheating.
Pour the marinara sauce into a plastic cup and place in the microwave for about 2 minutes, until hot.
Pour flour into a plate. Pour eggs into another plate and beat lightly with a fork. Pour bread crumbs into the third plate. Sprinkle the eggplant slices with salt. First coat the eggplant slices in flour, then in the egg, and then in the breadcrumbs.
Grease a baking sheet with vegetable oil and put the eggplant slices on it. Place the baking sheet in the oven and fry the eggplant for about 3 minutes on each side. Transfer the circles to a plate.
Put the slices of bread on a baking sheet, put 1 leaf of basil on each, a circle of eggplant on top, and again on a leaf of basil and a slice of eggplant, pour about 15 grams of cheese on top (for each slice).
Place the eggplant sandwiches under the grill for 3 minutes, until the cheese melts.
Pour 2 tablespoons of marinara sauce over each serving, garnish hot eggplant sandwiches with basil leaves.