1. Place eggplant rounds in an even layer on a baking sheet. Sprinkle with salt and let stand 10 minutes. Rinse under cold running water and pat dry with paper towels.

2. Place 1 piece of mozzarella on half of the eggplant, followed by 1 piece of basil; sandwich with remaining eggplant.

3. Heat oil in a deep saucepan until it reaches 325 degrees on a deep-fry thermometer. Place flour, eggs, and breadcrumbs each in separate shallow dishes. Coat each eggplant sandwich evenly with flour, shaking off any excess. Then dip in eggs, followed by breadcrumbs to coat.

4. Working in batches, gently place eggplant sandwiches into hot oil and fry until golden brown, 2 to 3 minutes. Transfer to a paper-towel-lined plate. Cut each sandwich into 4 equal portions; serve with tomato sauce.