Grab the large bowl OR the bowl of a stand-up mixer (using the paddle attachment) with the melted/espresso butter in it. To that bowl, add the brown sugar and white sugar. Beat together until nice and fluffy, about 3 minutes. Add the eggs, one at a time, until combined. Pour in the vanilla extract and beat once more.
In one batch, add the flour. You will probably have to lift up the head part of your mixer to be able to add it all at once. Cover the mixer with a clean kitchen towel and turn it on low speed. Mix until the flour is mostly combined and then increase speed until you no longer see any flecks of flour. Pour in the chocolate chunks and mix one last time. Transfer the dough to the fridge to chill for an hour or up to 2 days.
Preheat oven to 350 degrees F. Line two baking sheets with parchment paper.
Using a medium cookie scoop, scoop out balls of dough. If it’s super chilled, you may need to push some dough into the scoop so it’s nice and compact and then release the lever. I like to add all the balls of cookie dough to a sheet of parchment versus scooping dough, as I bake.
Transfer 6 to 7 balls of dough onto the prepared baking sheet, spacing them a part because these do spread. Place in the oven and bake for about 7 to 8 minutes. If the dough is super cold, it may need up to 10 minutes to bake. They should be light to medium golden brown. Sprinkle with a few pinches of salt upon exiting the oven. Repeat until you’ve baked all the cookies.
To freeze, add the cookie dough balls to a baking sheet and stick in the freezer until very cold, about 20 minutes and then transfer to a freezer-safe plastic bag.