1 tablespoon red wine vinegar
1 tablespoon fresh lemon juice
2 teaspoons fresh oregano, chopped, or 3/4 teaspoon dried oregano
1/2 teaspoon salt
1/4 teaspoon freshly ground black pepper
2 1/2 tablespoons extra-virgin olive oil
1 large eggplant, about 1 1/2 pounds, trimmed and cut into 1/2-inch cubes
1 pound spinach, stemmed and torn into bite-sized pieces
1 cucumber, peeled, seeded, and diced
1 tomato, seeded and diced
1/2 red onion, diced
2 tablespoons black Greek olives, pitted and chopped
2 tablespoons crumbled feta cheese