Preheat oven to 400°F (204°C) and line a baking sheet with parchment paper.
Slice eggplant into 1/4-inch thick sheets with a mandoline; select 12 center slices.
Arrange eggplant on the baking sheet, brush with olive oil, and season with salt and pepper.
Roast for 15-20 minutes until soft; pat dry with paper towels.
Mix ricotta, spinach, parmesan, egg, Italian seasoning, salt, and pepper in a bowl.
Spread 1/2 cup marinara in a baking dish. Fill and roll eggplant slices, placing them seam side down in the dish.
Top with remaining marinara and mozzarella. Bake for 15 minutes, broil for 3-4 minutes, and garnish with basil.