In a small bowl, whisk together the flour, baking soda, and salt. Set aside.
In the bowl of a stand mixer fitted with the paddle attachment, beat the butter, brown sugar, and granulated sugar on medium-high until light and creamy, about 3 minutes (it should resemble fluffy frosting).
Add the eggs and vanilla and mix on low until completely combined, scraping down the bowl as needed.
Add the flour mixture all at once and mix on low until just combined (stop mixing as soon as there are no dry spots of flour in the dough - do not overmix).
Add the chocolate chips and mix into the batter on low just until combined.
Transfer the mixing bowl to the refrigerator and refrigerate for 20 minutes while the oven heats. (This step is important as the cold dough is key to the soft centers of the cookies.)
Heat oven to 350°F / 177°C.
Lightly grease a sheet pan or line it with a Silpat baking mat or parchment paper.
Use a tablespoon measuring spoon (use the measuring spoon as a guide, but make these “heaping” tablespoons with dough rounded over the top) to scoop out even portions of cold cookie dough. (Note: Be sure that the cookie dough is about the size of a golf ball. If the cookies are smaller than this they won't spread out enough to have soft, chewy centers.)
Arrange the cookie dough on the prepared sheet pan, leaving space for the cookies to spread out.
Bake the cookies until the edges are just starting to turn golden brown and the centers are still very pale and soft (they will continue to firm up and darken after you remove them from the oven), 9 to 12 minutes.
When you remove the sheet pan from the oven, tap it firmly on the kitchen counter a few times to deflate the cookies (this step helps to give the cookies lightly crinkled edges and a dense center).
Sprinkle the tops of the cookies with flaked sea salt (this is optional and you may not need the full amount; just add a small pinch on top of each cookie if you want that salty crunch).
Leave the cookies on the sheet pan to cool for 5 minutes before transferring them to a cooling rack. (Note: If you try to move them too early they may fall apart, but will firm up as they cool.)
Store cookies in a sealed container at room temperature for up to 3 days.