Preheat your oven to 400°F (200°C).
In a large bowl, whisk together all-purpose flour, cake flour, baking soda, baking powder, cornstarch, and salt until well combined.
In the bowl of a stand mixer fitted with a paddle attachment, add cubed cold butter and begin creaming it on medium-low speed for about 30 seconds. Gradually add in brown sugar followed by white sugar, mixing each addition until light and fluffy.
Add in one large egg along with an additional egg yolk (and vanilla extract if using). Blend until fully incorporated; scrape down any butter stuck on the paddle attachment as needed.
With the mixer set to low speed, gradually add in your dry flour mixture until just incorporated. Then fold in chocolate chips gently until evenly distributed throughout the dough.
Measure approximately six cookies each weighing around 5.7 oz., keeping them nice and tall before placing them on a prepared baking sheet. Bake for about 10-12 minutes or until golden brown on top.