Preheat the air fryer to 310ºF.
In a medium bowl, whisk together the almond flour, sweetener, collagen, baking soda, and salt.
Stir in the butter, egg yolk, and vanilla extract until well combined.
Stir in the chocolate chips.
Gather the dough into a ball and place on a square of parchment paper about 8 inches square.
Pat into a disc about 5 inches in diameter.
Set the air fryer to Bake and set the cookie on the air fryer crisper rack.
Cook at 310ºF for 8 to 10 minutes, until puffed and golden brown.
Remove and let cool completely.
