Heat 2 tablespoons oil in large skillet over medium heat. Add diced eggplant, a little at a time, and cook until golden brown, adding remaining oil as needed.
Drain eggplant on paper towels. Add red pepper and cook until tender-crisp. Drain on paper towels. Separate pita breads, pulling completely apart into halves. Arrange on baking sheet, cut sides up.
Spread 2 tablespoons spaghetti sauce on each pita bread half. Top with some of eggplant, red pepper, pepperoni and onion slices. Bake at 400° F for 5 minutes.Servings: 6