In the bowl of a stand-up mixer, cream together the butter, sugar, and brown sugar on medium speed until you have a light fluffy mixture.
At low speed, add in the eggs, vanilla extract, the lemon juice and blend until all incorporated. Then increase speed to medium and mix for an additional 2 minutes until the mixture is light and fluffy.
In a separate mixing bowl, mix the flour, oats, baking soda, salt, and cinnamon together until all blended.
Whisk into the flour mixture the chocolate chips and the walnuts until they are coated.
Slowly incorporate the flour mixture into the buttery mixture and mix at low speed until blended, but do not overmix.
With a medium cookie scoop, scoop the dough into balls and place it in the air fryer basket.
Cook in the air fryer on a manual setting at 300 degrees F for 8 to 9 minutes until the cookies has a golden edge
Let the cookie cool in the basket for a few minutes then transfer to a cooling rack.
