01 - Preheat the oven to 350°F. Lightly grease a 10-inch ovenproof skillet, preferably cast iron.
02 - In a medium bowl, whisk together flour, baking soda, and salt.
03 - In a large bowl, whisk melted butter, granulated sugar, and brown sugar until smooth and well blended.
04 - Add the egg and vanilla extract to the wet mixture and whisk until fully incorporated.
05 - Gradually stir the dry ingredients into the wet mixture until just combined.
06 - Fold in chocolate chips and nuts, if using.
07 - Spread the dough evenly into the prepared skillet.
08 - Bake for 22 to 25 minutes until the top is golden and edges are set, leaving the center slightly soft.
09 - Allow to cool for 5 minutes. Serve warm, optionally topped with ice cream.