Slice eggplant crosswise into ½” rounds. Toss with a pinch of salt and set aside to drain in a colander.
Meanwhile, heat oven to 350 degrees F.
Warm the tomato sauce over low heat in a small saucepan, set aside.
Pour the flour into a wide bowl or dish, crack and beat the eggs into another similar dish, and pour the breadcrumbs and parmesan into a third dish and mix well.
Meanwhile, heat the canola oil in a wide pan over medium-high heat.
Once eggplant has drained, pull and pat dry. Dip each pieces into the flour to coat evenly, then the egg, then breadcrumb mixture.
Pan fry in the canola oil without letting the pieces touch, about 3 minutes on each side. Set each aside on a towel to drain.
Pour half the tomato sauce in a baking dish, spread the fried eggplant over evenly, then top with the remaining tomato sauce. Sprinkle extra parmesan over, and layer the mozzarella on top.
Bake for 18-20 minutes or until the mozzarella is melted.
Serve with your favorite grilled vegetables or salad.