Melt butter in a medium saucepan over medium-high heat. Cook, gently swirling pan constantly, until particles begin to turn golden brown and butter smells nutty, about 5 minutes. Remove from heat and continue swirling the pan until the butter is a rich brown, about 15 seconds longer. Transfer to a medium bowl, whisk in ice cube, transfer to refrigerator, and allow to cool completely, about 20 minutes, whisking occasionally. (Alternatively, whisk over an ice bath to hasten the process.)
Meanwhile, whisk together flour, baking soda, and salt in a large bowl. Place granulated sugar, eggs, and vanilla extract in another large bowl and mix with a handmixer until mixture is pale brownish-yellow and falls off the whisk in thick ribbons when lifted, about 5 minutes.
When brown butter mixture has cooled (it should be just starting to turn opaque again and firm around the edges), add brown sugar and cooled brown butter to egg mixture and Mix on medium speed to combine, about 15 seconds. Add flour mixture and mix on low speed until just barely combined, with some dry flour still remaining, about 15 seconds. Add chocolate and mix on low speed until dough comes together, about 15 seconds longer. Transfer to an airtight container and refrigerate dough at least overnight and up to 3 days.
On the next day, get a scale and meassure 40g balls of cookie dough and place into a container. Divide layers with parchment paper, label and put into the fridge