Preheat your oven to 350°F.
In a medium bowl, whisk together the flour, baking soda, and salt.
In a large mixing bowl, cream together the softened butter, brown sugar, and granulated sugar until light and fluffy.
Add the vanilla extract and eggs, one at a time, mixing well after each addition.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Fold in the chocolate chips and nuts, if using.
Transfer the cookie dough to a 10-inch cast-iron skillet or oven-safe pan, spreading it evenly.
Bake for 25-30 minutes, or until the edges are golden brown and the center is set.
Allow to cool for 10 minutes before slicing and serving warm.