Preheat oven to 375 °F (191 °C) and line 2 large baking sheets with parchment paper or silicone baking mats.
Whisk the flour and baking soda together in a medium bowl and set aside.
In a small skillet over medium high heat, melt 10 tablespoons of butter and continue cooking until the butter is a dark golden brown and has a nutty aroma. This will take about 1-3 minutes, but you'll need to constantly swirl the skillet and watch it otherwise it'll burn!
Transfer the brown butter to a heatproof bowl and then stir in the remaining 4 tablespoons of butter into the hot butter until it's completely melted.
In the bowl of a stand mixer, add both sugars, salt and vanilla. Pour in the butter and beat until well incorporated. Add the egg and egg yolk and mix until smooth, with no sugar lumps in it.
Let the mixture stand for 3 minutes then beat on high for 30 seconds. Repeat the process of resting and beating 2 more times until the mixture is thick and smooth.
Stir in the flour mixture until just combined then stir in the chocolate chips by hand.
Using a medium sized cookie scoop, scoop dough onto prepared cookie sheet and arrange them about 2 inches apart.
Bake for 10-12 minutes or until the edges are crispy and the inside is still soft.
Let cookies sit on cookie sheet for 5 minutes before transferring to a wire cooling rack to cool completely. Sprinkle sea salt on top to finish, if desired.