This is my recipe for the crispiest sweet potato fries in the air-fryer. Cornstarch is absolutely essential to get the crispy texture that we know and love.
Peel and cut the sweet potatoes into ½-inch thick fries (¼ for extra-crispy).
Add the sweet potatoes to a large bowl of cold water and let them soak for 10 minutes. This will prevent them from burning as much. Drain and dry them thoroughly with a dish towel.
In a large bowl, combine the olive oil, garlic powder, onion powder, salt, cornstarch, and 2 teaspoons of water. Mix to form a slurry.
Add the sweet potatoes to a bowl and toss to thoroughly coat the fries.
Preheat your air-fryer to 400°F. Add half the fries to the basket with a little space between each fry. Spray with oil and cook for 18-20 minutes, shaking the basket halfway through. Transfer the fries to a wire rack and repeat with the other half. Enjoy!