Heat the air fryer (or oven) to 400 degrees. In a bowl, spray the potatoes with oil and season with the salt, pepper and garlic powder. Toss to coat evenly.
Place the potatoes in the heated air fryer and cook (on air fry setting) at 400 degrees for 25 minutes.
While the potatoes cook, in a bowl whisk together the dressing ingredients and set aside.
Once the potatoes are done, let them sit at room temperature for 5 minutes before adding to the dressing. Gently toss to coat, and let the potatoes sit at room temperature for another 10-20 minutes, gently tossing to keep the dressing moving around all the potatoes.