Bring a large pot of lightly salted water to a boil. Add pasta and cook for 8 to 10 minutes or until al dente; drain. Keep warm.
Meanwhile, heat the olive oil and butter in a skillet over medium heat. Add the garlic; cook and stir until softened. Mix in the eggplant. Let the eggplant cook for 5 minutes without stirring. Then stir and cook until tender, about 5 more minutes.
Mix in the spinach and season with salt, and pepper. Cook, stirring occasionally, for 3 minutes. Stir in the drained pasta and lemon juice along with 1/2 cup Parmesan cheese. Transfer to a serving dish and top with remaining cheese and cracked black pepper.