Preheat oven to 350°.
Cut each pita in half horizontally; cut each pita half into 6 wedges to form 72 wedges. Divide the wedges evenly among two baking sheets lined with parchment paper and coated with cooking spray. Lightly coat wedges with cooking spray. Sprinkle cheese and pepper evenly over wedges. Bake at 350° for 11 minutes or until crisp, rotating baking sheets after 5 minutes.