Prep the potatoes and onion: Wash and dry the potatoes thoroughly. Cut them into bite-sized cubes or wedges so they cook evenly. Peel and thinly slice the onion. The onion slices will caramelize slightly in the air fryer and add a sweet, savory flavor to the potatoes.
Season the vegetables: In a large bowl, toss the potatoes and onion with olive oil, garlic powder, smoked paprika, salt, black pepper, and dried herbs if using. Make sure each piece is evenly coated in oil and seasonings, which helps them crisp up beautifully in the air fryer.
Preheat the air fryer: Preheat your air fryer to 400°F (200°C) for 3–5 minutes. This ensures the potatoes start cooking immediately and develop a golden-brown, crispy exterior.
Cook the potatoes and onion: Place the potatoes and onion in the air fryer basket in a single layer for even cooking. Cook for 20–25 minutes, shaking the basket or stirring halfway through to ensure all pieces crisp evenly. The potatoes should be golden and tender on the inside, while the onions are soft and slightly caramelized.
Check and serve: Test a potato for tenderness by piercing with a fork. If needed, cook an additional 2–3 minutes for extra crispiness. Transfer the potatoes and onion to a serving dish and sprinkle a little extra salt or herbs on top for garnish. Serve warm as a comforting side dish for breakfast, lunch, or dinner.