1cupsemi-sweet chocolate chips plus more for topping
Instructions
In a large bowl, whisk together flour, baking soda, cornstarch, and salt.
With a mixer, beat the brown sugar and granulated sugar with the melted butter until the sugars have dissolved into the butter. Add in the egg and egg yolk and beat to combine. Add the tablespoon vanilla extract.
Slowly mix in the flour mixture until combined. Fold in the chocolate chips.
Cover with plastic wrap and chill in the refrigerator for at least an hour or overnight. If you don't have time to chill you can still make them right away they just won't have that super soft center.
When you’re ready to bake the cookies, pre-heat your oven to 325 degrees. Pull the dough out of the fridge and let it sit for about 10 minutes or longer.
Line baking sheets with parchment paper. The dough will be hard to roll but make balls about 2 tablespoons in size. Press additional chocolate chips on top for the bakery look.
Bake for 8-10 minutes or until they get just a touch of golden on top. They will look underdone.
Let the cookies cool for about 5-10 minutes before removing to cool completely on a wire rack. Store cookies in an airtight container.
Notes
Chilling allows the centers to stay soft while baking. I have baked them without chilling and they're still good but for the best results, chill. Source: slightly adapted from Center Cut Cook