Adjust oven rack to middle position and Pre-heat oven to 375 degrees with oven racks in center. Line 2 large baking sheets with parchment paper.

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

Melt 10 tablespoons butter in non-stick 10-inch skillet over medium-high heat. Once melted, continue cooking, whisking or swirling pan constantly until butter is dark golden brown and has nutty aroma, 1 to 3 minutes.

Remove skillet from heat and transfer browned butter to large heatproof bowl.

Whisk remaining 4 tablespoons butter into hot butter until completely melted.

Add both sugars, salt, and vanilla to bowl with butter and whisk until fully incorporated.

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. Repeat process of resting and whisking 2 more times until mixture is thick, smooth, and shiny.

Stir in flour mixture until just combined, about 1 minute.

Stir in chocolate chips, giving dough final stir to ensure no flour pockets remain.

Divide dough into 16 portions, each about 3 tablespoons.

Arrange dough 2 inches apart on prepared baking sheets, 8 dough balls per sheet.

Bake cookies one tray at a time until cookies are golden brown and still puffy, and edges have begun to set but centers are still soft, 10 to 14 minutes, rotating baking sheet halfway through baking.

Transfer baking sheet to wire rack; cool cookies completely before serving.