Preheat an air fryer to 375 degrees F (190 degrees C).

Bring a large pot of water to a boil; remove from heat.

Wash and dry chestnuts. Place flat-side down on a cutting board. Using a paring knife, score a large “X” on rounded side, covering at least half of chestnut. Make sure the knife goes through outer skin and brown layer underneath. This will aid in peeling after roasting.

Soak chestnuts in boiled water for 1 to 5 minutes, depending on size. Remove chestnuts with a slotted spoon and immediately transfer to the air fryer basket. Place 1 cup boiled water inside the basket.

Cook in the preheated air fryer for 10 minutes. Shake well. Check to see if there is still water inside. If not, add another 1/2 cup. Continue cooking until shells have peeled away and exposed flesh has browned, 5 to 10 minutes. Cool until able to peel shells completely.