Preheat oven to 350°F. Grease or line a 9x12 baking dish with parchment paper.
In a large bowl, whisk melted butter with brown sugar and cane sugar until well combined.
Add eggs, egg yolks, and vanilla. Mix until smooth.
In a separate bowl, whisk flour, baking soda, and salt. Add to wet ingredients and stir until just combined.
Fold in chocolate chips. Spread dough evenly into the prepared pan.
Sprinkle flaky sea salt over the top.
Bake for 22–25 minutes, until edges are golden and the center is just set.
Let cool for at least 30 minutes before slicing. Enjoy!