Preheat oven to 350°F-grease 6 (4-5 in) mini cast iron skillets with butter or cooking spray and place on baking sheet
In large mixing bowl, combine softened butter, granulated sugar and brown sugar.
Add egg and vanilla to butter mixture-stir until combined
In a separate bowl, whisk flour, baking soda and kosher salt
Add to butter mixture to flour mixture-stir just until combined- do not overmix
Fold in chocolate chips
Scoop dough into greased mini skillets- I use ice cream scoop, approx. 1/4 cup each
Sprinkle top with flaky salt, if desired
Bake 15 minutes or until golden brown
Cool for about 10 minutes- Serve with a scoop of ice cream!