In a small bowl whisk together first three dry ingredients. Cream butter in the bowl of a stand mixer to soften. Add sugars and mix until well combined, add eggs and vanilla and mix until light and fluffy. Add dry ingredients and chips and mix again thoroughly. Spray pan with non-stick spray and spread dough into an even layer, squishing the dough flat. Use a little water on your finger to smooth the top of the cookie for a nicer appearance if you are not going to frost the top.
Bake for 36 to 42 minutes (depending on pan size and oven temp.), until sheen on top disappears and a few cracks appear. Let cool completely before removing from pan.
Chef’s Note: Add the chocolate chips to the flour mixture; the chips stay softer after they are baked.