Adjust oven rack to middle position and preheat to 375°F. Line 2 large baking sheets with parchment paper.
Whisk flour and baking soda together in a medium bowl then set aside.
Heat 10 tablespoons butter in a small saucepan over medium heat until melted, about 2 minutes. You do not want the butter to get too hot, just melted. Remove pan from heat. Stir the remaining four tablespoons butter into the warmed butter until completely melted. Transfer to a mixing bowl.
Add both sugars, salt, and vanilla to bowl with the butter and whisk until fully incorporated. Add egg and yolk and whisk on medium-high speed until mixture is smooth with no sugar lumps remaining, about 30 seconds.
Let mixture stand 3 minutes. Whisk for 30 seconds and let stand another 3 minutes. Repeat the process of whisking and resting two more times until the mixture is thick, smooth and shiny (4 times total).
Using a rubber spatula or wooden spoon, stir in flour mixture until just combined, about 1 minute. Stir in white, semi-sweet and bittersweet chocolate chips, giving the dough a final stir to ensure no flour pockets remain.
Transfer mixing bowl to refrigerator and allow to chill for 15 to 30 minutes, or until dough is chilled and is easy to scoop and roll in your hands. The dough should not feel overly sticky.
Divide dough into 16 portions, each about 3 tablespoons and roll into a ball. If the dough starts to warm and get sticky as you roll, place the dough balls on a sheet tray and refrigerate for 15 minutes.
Tear the dough balls in half by pulling gently from both sides. Press the two halves together again, with the lumpy torn sides facing upward to expose the chips and give a more rustic appearance. Add a few more chips on top if desired so they pop out more after baking and look prettier.
Allow portioned dough to chill covered and refrigerated for 1 hour or longer on a sheet tray. Arrange dough 2-inches apart on lined baking sheets, eight dough balls per sheet. Smaller baking sheets can be used but will require baking three batches.
Bake cookies one tray at a time until cookies are golden brown and still puffy, and edges have set, but centers are still soft, 10 to 14 minutes. Rotate baking sheet halfway through baking.
The cookies will look slightly underdone in the center, but they will deepen in color and deflate slightly once cooled. Let cookies cool for 3 minutes on the baking sheet, then transfer to a wire rack to cool completely.
I've found that the cookie spread less the longer you can chill the cookie dough balls. Overnight is ideal!
Cookie dough can be shaped into balls and refrigerated in a resealable plastic bag for up to 1 week before baking. Just do the breaking apart step right before baking for a more rustic surface.
Cookies can be stored in an air tight container for up to 5 days.