In a saucepan over medium heat, melt the unsalted butter. Continue cooking, stirring frequently, until the butter turns a golden brown color and smells nutty. This should take about 5-7 minutes. Be careful not to burn it! Remove from heat and let it cool to room temperature.
Preheat your oven to 350°F (175°C) and line your baking sheet with parchment paper.
In a mixing bowl, whisk together the all-purpose flour, baking soda, and kosher salt. Set aside.
In a large bowl, combine the browned butter, dark brown sugar, and granulated sugar. Use a whisk or electric mixer to beat until well combined and smooth.
Add the eggs, one at a time, mixing well after each addition. Then, stir in the vanilla extract until fully incorporated.
Slowly add the dry ingredients to the wet mixture, stirring until just combined. Do not overmix! If the dough seems too wet, add a tablespoon of flour at a time until it reaches the desired consistency.
Gently fold in the chopped semi-sweet chocolate until evenly distributed throughout the dough.
Using a cookie scoop, drop rounded balls of dough onto the prepared baking sheet, spacing them about 2 inches apart. Bake in the preheated oven for 10-12 minutes, or until the edges are golden brown but the centers are still soft.
Remove the cookies from the oven and let them cool on the baking sheet for 5 minutes before transferring them to a cooling rack. Enjoy warm or store for later!