• Preheat the air fryer to 350º F (on bake mode if your air fryer has that feature) and lightly grease an 8" springform cake pan with butter.
• In a medium mixing bowl, add the melted butter, then slowly add the brown sugar and granulated sugar while stirring with a spatula. Stir in the vanilla and add the egg, and mix until well combined. Then add the flour slowly, along with the baking soda, baking powder, and salt and mix until you get a firm dough consistency. Once the dough has formed, fold in the chocolate chips.
• Place the dough into the cake pan and press down to form a flat layer. You can use a container with a flat bottom to press down the dough. Cover the cake pan with foil and place it inside the air fryer without the basket.

  Removing the air fryer basket was crucial to make the 8” spring form pan fit inside the air fryer. For smaller air fryers, you may consider using a smaller cake pan.
• Bake the cookie cake for 20 minutes, covered with aluminum foil. After 20 minutes, remove the foil, reduce the temperature to 250º F, and continue baking for 10 more minutes. Remove the cookie cake from the air fryer immediately and let it rest on a cooling rack for at least 30 minutes, allowing it to cool to room temperature completely before removing it from the pan.

Frosting

• Add the butter to a medium sized mixing bowl and beat with a hand mixer on medium-high speed for about 2 minutes or until you get a smooth and creamy consistency. Add the milk, vanilla, and salt and mix for 3 minutes. Then, slowly add the powdered sugar while mixing until you get the right frosting consistency.

  Add one tablespoon of milk or powdered sugar at a time to adjust the consistency.
• Add the frosting to a pipping bag with a star tip and decorate the cookie cake after it's completely cooled, then add the sprinkles.