1. Line 2 to 3 rimmed cookie sheets with parchment paper and set aside.
2. In a large bowl mix together butter, sugar, brown sugar until smooth. Add eggs until well combined. Beat in the vanilla. (If using a KitchenAid electric mixer, use paddle attachment).
3. In a medium bowl, whisk together the flour, baking soda and kosher salt. Add to the butter mixture and beat on low speed until just combined, scraping down the sides of bowl at least once to ensure all ingredients mixed together.
4. Stir in ¾ bag of chocolate chunks.
5. Using an ice cream scoop or 2 tablespoon cookie scoop, scoop dough into 20-24 balls on parchment paper lined cookie sheets (about 8-12 dough balls per sheet). Press a few of the remaining chocolate chunks into the top of each ball of cookie dough.Press down on the top of each ball of cookie dough gently with the palm of your hand to flatten slightly. Cover with plastic wrap and refrigerate for at least 30 minutes.
6. Preheat oven to 350º.
7. Bake for 13-15 minutes or until cookies start to turn golden brown and crisp around the edges buy still a little under-baked/doughy in the middle. You'll also want to rotate the cookie sheet after 8 min of baking.
8. Once cookies are done, remove from oven and sprinkle each cookie with a pinch of coarse sea salt.
9. Let cookies cool for 10 minutes before transferring to a cooling rack or enjoying them.