For the cookie dough

• Preheat the Oven: Preheat your oven to 370°F. Line a baking sheet with parchment paper.
• In a medium saucepan, melt the butter over medium heat. Continue cooking, swirling the pan occasionally, until the butter foams and turns a rich amber color with a nutty aroma, about 5-7 minutes. Watch closely to avoid burning. Once browned, immediately transfer the butter to a large heatproof bowl and let it cool to room temperature. I let my cool down for about 45 minutes!
• Once the better has cooled down, combine the cooled brown butter, dark brown sugar, and white sugar. Use a whisk and whisk the ingredients until evenly combined and well incorporated. About 30-45 seconds.
• Add the whole egg, whisk until evenly combined, then add the egg yolk, and whisk again until evenly combined. Add the vanilla extract and mix just until incorporated.
• Add together the flour, baking soda, baking powder, salt, chocolate chip and switch to a rubber spatula to gently fold the dough until there are no more flour streaks. DO NOT OVER WORK THE DOUGH.
• Scoop the dough using a 3-tablespoon-sized cookie scoop. For larger cookies, scoop two balls and press them together to form one larger ball, or simply use one scoop for a smaller cookie. Roll the dough into balls and place them on the prepared baking sheet. If making larger cookies, place 6 dough balls on the sheet, spacing them about 3 inches apart. For smaller cookies, you can place 9 dough balls on the sheet, spacing them accordingly.
• Bake in the preheated oven for 13-15 minutes for larger cookies or 9-11 minutes for smaller cookies, until the edges are golden brown and the centers are still slightly soft. If desired, sprinkle a pinch of flaky salt on top of each cookie immediately after removing them from the oven.
• Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.