Preheat oven to 325 and grease a 9x13 pan.
In a bowl, combine flour, salt, and baking soda.
In a large bowl, whisk melted butter, brown sugar, and sugar. Add egg, egg yolk, and vanilla. Whisk until combined.
With a rubber spatula, fold in the dry ingredients. When about half-way combined, add the chocolate chips and continue to mix. DO NOT OVER MIX.
Drop the dough (it will be very thick) onto the prepared pan. Use your fingers or a spoon to pat down the dough. It doesn't have to be perfect.
Bake for about 22 minutes. Remember, if you want them chewy, do not over bake.
Let cool to room temperature and then enjoy!