Prep the potatoes: Wash and peel the sweet potatoes (peel is optional—leave it on if you like a rustic texture). Slice into even planks, then into 1/4-inch sticks. Keep them as uniform as possible for consistent cooking.

Soak briefly (optional but helpful): For extra crispness, soak the cut fries in cold water for 15–20 minutes. This pulls off some starch and helps them brown better. Drain and pat completely dry with a clean towel.

Preheat the air fryer: Set to 380°F (193°C) and let it preheat for at least 3–5 minutes. A hot basket helps prevent sticking and improves texture.

Season and coat: In a large bowl, toss the fries with oil until lightly coated. Sprinkle on cornstarch, salt, pepper, garlic powder, paprika, and cayenne. Toss again until the seasoning is evenly distributed and no dry cornstarch clumps remain.

Arrange in batches: Place fries in a single layer in the air fryer basket. Leave a little space between fries for airflow. Work in 2–3 batches as needed.

Cook the first side: Air fry at 380°F (193°C) for 8 minutes. Shake the basket or flip the fries halfway through so they brown evenly.

Crisp and finish: Increase temperature to 400°F (204°C) and cook for 2–4 more minutes, watching closely. Pull them when edges are browned and centers are tender.

Season to taste: While hot, sprinkle with a pinch more salt if needed. Repeat with remaining batches.

Serve: Enjoy right away with your favorite dip. For a sweet-savory twist, dust with a little cinnamon and salt instead of paprika.