Fill a large pot with lightly salted water and bring to a rolling boil over high heat. Cook the pasta uncovered, stirring occasionally, until the pasta has cooked through but is still firm to the bite, about 11 minutes. Drain well in a colander set in the sink, reserving 1 cup pasta water.
Heat 2 tablespoons olive oil in a large frypan over medium heat. Stir in eggplant and garlic and drizzle with remaining olive oil to coat; cook and stir until the eggplant is tender and lightly browned, 5 to 7 minutes. Season with salt and pepper. Stir in the sun-dried tomato spread and tomato sauce; cook and stir until heated through, about 5 minutes more. Add penne and toss. Stir in pasta water if the sauce is too thick. Sprinkle with basil before serving.