Preheat your air fryer to 375°F (190°C).
Place one graham cracker square into the air fryer basket.
Top with a square of chocolate and a marshmallow.
Air fry for 3–4 minutes or until the marshmallow is golden brown and slightly melted.
Remove carefully and top with the second graham cracker square to form a sandwich.
Let cool for 1–2 minutes before enjoying!