In a small bowl combine the flour, baking soda and salt. Mix and set aside.
In a stand mixer fitted with a paddle attachment or with a hand mixer cream together the butter and both sugars until light and fluffy.
Next add in the vanilla and eggs. Mix until combined. Add in the flour mixture and mix just until combined and you no longer see any flour bits. Lastly stir in the chocolate chips by hand using a wooden spoon or silicone spatula.
Spray a 10-inch cast iron skillet with cooking spray. Making sure to get the sides and bottom. Scoop in the batter and press down so it forms an even layer. If you lightly wet your hands with water it helps to keep the dough from sticking when you press it. Sprinkle the top with the flaked sea salt.
Bake for 60-65 minutes or until set in the middle and golden brown around the edges. Remove and let sit for 10 minutes before slicing. Serve warm with ice cream or whipped cream.