Brown 10 tbsp butter in a large (10-14 in) skillet over medium-high heat. Keep butter swirling for even heating, until it is dark golden brown and has a nutty aroma. The most important indicator of done-ness is smell and look, not time. (could go for as long as 10 mins).
Pour hot butter into a heatproof bowl and mix in remaining 4 tbsp until melted.
Add brown sugar, granulated sugar, vanilla and salt to melted butter, whisk until fully incorporated.
Add egg and yolk, whisk until mixture is smooth with no lumps; roughly 30 seconds.
Let mixture stand for 3 minutes, then whisk for 30 seconds. Repeat this 2 more times until the mixture is thick, smooth, and shiny. It should look and feel noticeably different between the first whisking and the last.
Add flour and baking soda to the wet mixture, mixing until just combined (a minute or less).
Stir in chocolate chips, mixing only enough to incorporate and eliminate any flour pockets.
Working with 1 1/2 - 3 tbsp dough at a time, roll into balls and space them 2 inches apart on baking sheets with parchment paper.
Bake, one sheet at a time, for 10-14 minutes, rotating the sheet halfway through. The perfect time to pull from the oven is when the cookies are golden brown and edges have begun to set (they’ll start to look dry). The centers will still be soft at this point.
With 1 1/2-2 tbsp dough for more cookies, the bake time is 10 minutes or less, and very vulnerable to over cooking.
After baking, transfer cookies to a wire rack and garnish with sea salt for added flavor. After cooling and feasting.