Preheat the oven to 350 degrees F. Lightly grease a 10-inch cast iron skillet with butter or avocado oil.

In a stand mixer, cream together the butter, pure maple syrup, eggs, and vanilla extract. Mix with the paddle mixer until creamy. 

Add the coconut flour, tapioca flour, baking powder, and sea salt and mix until combined. Add in the chocolate chips and mix until the chocolate chips are incorporated.

Transfer the cookie dough to the prepared skillet and smooth into an even layer. Bake on the center rack of the oven 25 to 30 minutes, or until the cookie is cooked through but still slightly gooey in the center.

Remove from oven and allow cookie to cool 10 minutes before slicing and serving. You can also plop a few scoops of ice cream in the center and hand everyone spoons to share.