Preheat the oven to 375°. Spray a small casserole dish with vegetable spray and set aside.
Cut the stems and heel of the egg plant, then slice the eggplant into 1/2" thick slices from root to tip. Place the slices on a wire rack sitting on a sheet pan. Sprinkle with kosher salt and let sit for 15 minutes. Flip the eggplant and sprinkle the other side with salt and sit for another 15 minutes. Rinse the salt off the eggplant then dry thoroughly with paper towels.
Heat a large griddle pan over medium high heat. Add the olive oil and turn the pan to coat with the oil. Working in batches, lay the eggplant onto the hot grill pan and cook on one side for 4-5 minutes until tender and grill marks appear. Flip the eggplant and continue to cook for an additional 4-5 minutes. Transfer to the wire rack to cool while you cook the remaining eggplant.
For the Cheese Filling:
While the eggplant is resting with the salt (step 2) make the filling. In a medium bowl, combine the cottage cheese, 1/2 cup mozzarella, 1/4 cup grana padana, the egg, salt and pepper. Stir to combine. Add the fresh herbs and lemon zest, stirring until herbs are evenly distributed in the filling.
Assemble the rollatini
Spoon 1/4 cup of marinara sauce into the bottom of the casserole dish and spread it around with the back of a spoon.
Lay a slice of eggplant (short end facing you) on a work surface. Add a mounded tablespoon of ricotta filling about 1 1/2" from the bottom of the eggplant and carefully fold the bottom over the filling and continue rolling the eggplant up into a tight roll. Transfer the eggplant to the casserole dish and continue in this fashion until you've used up the eggplant and filled the dish.
Spoon the remaining marinara over the tops of the rollatini. Garnish with remaining Mozzarella and Grana Padana. Bake uncovered for 20-25 minutes or until bubbly and fragrant.
Let the dish sit for 5-10 minutes before serving. Sprinkle with more chopped basil if desired.