Instructions

1. Preheat the oven to 350°F and generously butter a 12 inch cast iron skillet allllll over.  Set aside.
2. Place the butter and brown sugar in a stand mixer fit with the paddle attachment. Mix together until smooth and glossy.
3. Scrape down the sides of the bowl and add the egg and vanilla extract. Mix until combined.
4. Scrape down the bowl and add the cocoa powder, espresso powder, flour, baking soda and salt. Mix on low speed, gradually increasing to medium. Mix until just combined and no streaks of flour remain.
5. Fold in the chocolate. Do not over mix!
6. Transfer the cookie dough into your prepared skillet and pat it down into an even layer all the way to the edges.
7. Bake at 350°F for 30 to 40 minutes or until the edges are set but the center is still gooey. Allow to cool for 10 minutes before topping with vanilla ice cream and devouring! Enjoy!