Preheat and prep. Preheat your air fryer to 320°F (160°C) for about 3 minutes. Line the air fryer basket with a piece of parchment that fits flat and has a few holes poked in it for airflow. Lightly mist with oil if your parchment isn’t nonstick.

Mix the wet ingredients. In a medium bowl, whisk the peanut butter, granulated sugar, brown sugar, egg, melted butter, and vanilla until smooth and glossy.

Combine the dry ingredients. In a separate small bowl, stir together the flour, baking soda, and salt. Add this to the peanut butter mixture and fold until just combined. If using chocolate chips or chopped peanuts, fold them in now. The dough will be soft but scoopable.

Chill briefly (optional but helpful). If the dough feels sticky, chill it for 10–15 minutes. This makes it easier to handle and helps the cookies hold shape in the air fryer.

Shape the cookies. Scoop 1-tablespoon portions and roll into balls. For a classic look, roll each ball in a little granulated sugar, then use a fork to press a crisscross pattern on top, flattening each to about 1/2 inch thick.

Arrange and cook. Place 6–8 cookies in the basket, leaving space between them for air circulation. Air fry at 320°F (160°C) for 6–8 minutes until the edges look set and lightly golden. The centers may still look soft—this is good.

Cool to set. Let the cookies rest in the basket for 3–4 minutes, then transfer to a rack to cool completely. They’ll firm up as they cool. Repeat with the remaining dough.

Finish (optional). While warm, sprinkle with a tiny pinch of flaky salt for a sweet-salty pop.