Peel and cut the sweet potatoes into evenly sized fries.
Soak in cold water for 20 minutes to remove excess starch.
Drain well and pat completely dry with a towel.
In a bowl, toss the fries with cornstarch until lightly coated.
Add olive oil, salt, paprika, garlic powder, and Cajun seasoning. Toss again to coat evenly.
Place fries in the air fryer basket in a single layer. Cook at 375°F for 15–20 minutes, shaking halfway through. (Adjust time depending on fry thickness and crispiness preference.)
Serve hot and enjoy!