Prep the pan and air fryer: Lightly grease your pan and line the bottom with a parchment circle if you have one. Preheat the air fryer to 320°F (160°C) for 3–5 minutes.
Cream the butter and sugars: In a mixing bowl, beat the softened butter with granulated and brown sugars until light and fluffy, about 1–2 minutes.
Add egg and vanilla: Mix in the egg and vanilla until smooth. Scrape the bowl so everything combines evenly.
Combine dry ingredients: In a separate bowl, whisk flour, baking soda, baking powder, and salt.
Make the dough: Add the dry ingredients to the wet and mix just until combined.
Fold in chocolate chips and nuts if using. The dough will be thick.
Press and level: Spread the dough into the prepared pan, pressing to the edges in an even layer. Sprinkle a few extra chips on top for a bakery look.
Air fry: Place the pan in the air fryer basket and cook at 320°F (160°C) for 14–18 minutes.
Start checking at 14 minutes. The edges should be set and golden; the center should look slightly soft.
Rest and finish: Let the cookie pie cool in the pan for at least 10–15 minutes so it sets. Sprinkle with flaky sea salt if you like.
Slice warm or at room temperature.
Serve: Enjoy as-is or top with vanilla ice cream and a drizzle of chocolate or caramel sauce.