01 -
In a stainless steel pan over medium heat, cook the butter until the solids turn dark golden (about 10 minutes). Pour it all, including the browned bits, into a bowl.
02 -
Stir in the ground coffee and leave it alone to cool down to room temperature (roughly 20 to 30 minutes).
03 -
Whisk brown and white sugars together with the cooled butter mix for one minute until blended.
04 -
Whisk the egg, extra yolk, and vanilla into the sugar-butter mixture until smooth.
05 -
Carefully fold in the flour, baking soda, salt, and chocolate, stopping as soon as everything comes together.
06 -
Portion the dough out onto a baking sheet with parchment paper, then freeze it for 3 to 4 hours minimum (longer is better, overnight if you can).
07 -
Heat your oven to 350°F (180°C). Leave 2 inches between frozen dough balls on the baking tray and cook them for 10–12 minutes. The edges should look golden while the centers stay pale and puffy.
08 -
Set the baking tray on a cooling rack and let the cookies cool down there.