Whisk eggs in a small bowl until smooth. Pour bread crumbs into a shallow dish. Dip each tomato slice in egg and coat with bread crumbs. Arrange on baking sheets in a single layer.
Bake in the preheated oven until golden, about 5 minutes per side.
Pour 3 cups spaghetti sauce into the bottom of a 9x13-inch baking dish. Top with a layer of tomato slices. Layer half of the mozzarella cheese and Parmesan cheese on top. Repeat layers with remaining spaghetti sauce, tomatoes, mozzarella cheese, and Parmesan cheese. Sprinkle basil on top.
Bake in the preheated oven until golden brown, about 35 minutes.