Step 1

Combine Cup4Cup, cornstarch, baking powder, and baking soda in a small bowl and set aside.

Step 2

In the bowl of your stand mixer, fitted with the paddle attachment, combine the butter, both sugars, vanilla extract, and salt.

Step 3

At a low-speed mix to combine, increase the speed to medium and mix until light and fluffy - this should take around 4-6 minutes.

Step 4

Turn off your mixer, scrape down the sides of your bowl and the paddle to ensure everything gets incorporated equally.

Step 5

With your mixer running on low, add the egg and the egg yolk one by one and make sure to let them incorporate fully.

Step 6

Turn off your mixer, scrape down the sides of your bowl and the paddle to ensure everything gets incorporated equally.

Step 7

With the mixer running on low, add the flour and mix to combine. Add the chocolate and nuts and mix.

Step 8

Line a cookie sheet with parchment paper and portion the dough in 6oz cookies using your kitchen scale. Wrap the sheet tray with plastic wrap and refrigerate for 12hrs to allow the dough to rest. During this process the flour hydrates and develops flavor.

Step 9

Preheat your oven to 375F.

Step 10

Arrange 4 cookies on your parchment-lined sheet pan and sprinkle with flaky sea salt.

Step 11

Bake at 375F for 10 minutes, rotate the tray and reduce the temperature of your oven to 350F.

Step 12

Bake for an additional 6-9 minutes until they have crispy edges, look puffy, and still look slightly underdone in the center. If you want a gooey cookie you will want to underbake them.

Step 13

Remove the cookies from the oven and allow them to cool on the sheet tray for 5-10 minutes. Those cookies taste the best when eaten when they are freshly baked.

Step 14

Repeat with the rest of your cookie dough or freeze for future cookie cravings.