In a small bowl, mix together the oil, cumin and garlic powder. Brush each pita with the oil mixture. Stack the pitas on top of each other. Cut into 8 wedges per pita. Spread the wedges on a baking sheet in a single layer. Sprinkle with the flaky sea salt and 1/2 teaspoon pepper. Bake until lightly browned and crispy, 13 to 15 minutes.