Eggplant Rollatini

Cooking spray
2 large eggplants (about 1 pound each), trimmed
2 tablespoons extra-virgin olive oil
1 cup whole-milk ricotta cheese
⅔ cup shredded low-moisture part-skim mozzarella cheese, divided
4 tablespoons grated Parmesan cheese, divided
1 large egg
2 tablespoons chopped fresh basil, plus more for garnish
1 large clove garlic, grated with a microplane
1 teaspoon grated lemon zest
⅛ teaspoon salt
⅛ teaspoon ground pepper
2 cups baby spinach, chopped
1 (24-ounce) jar lower-sodium marinara, divided

Preheat oven to 425°F. Line 2 large rimmed baking sheets with parchment paper and coat the parchment with cooking spray. Slice the eggplants lengthwise into 18 (1/4-inch-thick) planks. Arrange the slices in a single layer on the prepared baking sheets; drizzle the tops evenly with oil and coat with cooking spray.
Bake until just tender, about 10 minutes. Remove from oven; do not turn oven off. Let the eggplant stand on the baking sheets until cool enough to handle, about 5 minutes.
Meanwhile, stir ricotta, 1/3 cup mozzarella, 3 tablespoons Parmesan, egg, basil, garlic, lemon zest, salt and pepper together in a medium bowl. Fold in spinach.
Coat a 9-by-13-inch baking dish with cooking spray. Spread 1 1/4 cups marinara in the bottom of the dish.
Spoon 2 tablespoons ricotta mixture on 1 end of 1 eggplant slice; roll up and place the roll, seam-side down, in the marinara in the dish. Repeat the process with the remaining eggplant slices and ricotta mixture. Pour the remaining 1 1/4 cups marinara evenly over the center of the eggplant rolls, leaving the roll ends exposed. Sprinkle the rolls with the remaining 1/3 cup mozzarella and 1 tablespoon Parmesan.
Cover the dish with foil. Bake until bubbling, 20 to 25 minutes. Remove the foil; bake until the top is slightly browned and the eggplant is very tender, 10 to 15 minutes. Let stand for 10 minutes. Garnish with additional basil, if desired.