How to Make It
Preheat oven to 475°F. Toss eggplant and olives with 3 tablespoons of the oil on a rimmed baking sheet. Roast in a single layer until eggplant is tender, 18 to 20 minutes.
Meanwhile, cook pasta according to package directions; drain well. Whisk together vinegar, salt, pepper, chopped oregano, and remaining 3 tablespoons oil in a small bowl.
Toss together pasta, eggplant-olive mixture, feta, tomatoes, and dressing. Garnish with oregano leaves.