Step 1Arrange eggplant slices in single layer on 2 baking sheets coated with cooking spray. Lightly spray tops with olive oil spray, then season with salt and pepper to taste. Broil eggplant on high, 1 sheet at a time, about 5 to 8 inches from heat source, until soft and lightly browned, about 2 1/2 minutes. Use spatula to turn slices, and season with salt and pepper. Broil 2 1/2 minutes more. Repeat with other baking sheet. Set aside.
Step 1Put ricotta, cheese, egg and basil in bowl of food processor and mix well, about 1 minute. Set aside.
Step 1Coat 8-inch baking dish with cooking spray. Spread 1 cup sauce in dish. Place 3 lasagna noodles over sauce, slightly overlapping. Spread 1/2 ricotta mixture over noodles. Top with 4 eggplant slices. Sprinkle eggplant with 1 cup mozzarella. Repeat layering. Finish with remaining sauce and grated Parmigiano-Reggiano cheese. Cover with plastic wrap. Refrigerate overnight. Let come to room temperature before baking.
Step 2Bake, uncovered, at 350 degrees until bubbling and lightly browned, about 55 minutes. Let rest 10 minutes. Cut into 6 squares. Serve hot or at room temperature.