Step 1

Whisk flour and baking soda together in medium bowl then set aside.

Step 2

Heat 10 tablespoons butter in 10-inch skillet over medium-high heat until melted, about 2 minutes. Continue cooking, swirling pan constantly until butter is golden brown and has a nutty aroma, 1 to 3 minutes.

Step 3

Remove skillet from heat and using a heatproof spatula, transfer browned butter to a large bowl or bowl of a stand mixer.

Step 4

Stir remaining 4 tablespoons butter into hot the butter until completely melted.

Step 5

Add sugars, salt, and vanilla to bowl with butter. Whisk until fully incorporated and fluffy.

Step 6

Add egg and yolk and whisk until mixture is smooth with no sugar lumps remaining, about 30 seconds. Let mixture stand 3 minutes, then whisk for 30 seconds on medium speed. Repeat the process of resting and whisking 2 more times until mixture is thick, smooth and shiny.

Step 7

Using a rubber spatula, stir in flour mixture until just combined. Stir in chocolate chips, giving dough final stir to ensure no flour pockets remain.

Step 8

Allow dough to chill for 15 to 30 minutes covered in the refrigerator so the dough can be easier to roll.

Step 9

Divide dough into 15 portions and roll into a ball, each about 3 tablespoons. Allow portioned dough to chill covered and refrigerated for 1 hour or longer on a sheet tray.

Step 10

Adjust oven rack to middle position and heat oven to 375°F. Line 2 large (18- by 12- inch) baking sheets with parchment paper.

Step 11

Arrange cookies 2-inches apart on prepared baking sheets, 8 dough balls per sheet. Add a few additional chips on top before baking for a prettier surface.

Step 12

Bake cookies 1 tray at a time in the middle of the oven until golden-brown and still puffy, and edges have begun to set, but centers are still soft, 10 to 12 minutes, rotating baking sheet halfway through baking.

Step 13

Allow cookies to cool for 10 minutes on the baking sheet, then transfer cookies to a wire rack. Cool cookies completely before serving.