Set your air fryer to preheat at 380 degrees Fahrenheit.
Carefully peel the potatoes and cut them into slices about one-quarter inch thick, trying to keep them uniform.
Combine the sliced potatoes in a large bowl with olive oil, salt, garlic powder, and black pepper, tossing until each slice is coated.
Arrange the potato slices in the air fryer basket in a single layer as much as possible.
Cook the potatoes for 15 minutes, turning them over once halfway through, until the outside is golden and crisp while the inside stays tender.
Garnish with fresh parsley if desired before serving.