01 - Melt butter in a medium saucepan over medium heat. Cook, stirring frequently, until butter foams, turns golden brown, and smells nutty (5–7 minutes). Transfer immediately to a large bowl to cool for 10 minutes.
02 - Whisk brown sugar and granulated sugar into cooled brown butter until well combined.
03 - Add eggs one at a time, whisking thoroughly after each addition. Stir in vanilla extract.
04 - In a separate bowl, whisk together flour, baking soda, and salt until evenly distributed.
05 - Gradually add dry ingredients to wet ingredients, stirring until just incorporated. Do not overmix.
06 - Fold in chocolate chips or chunks until evenly distributed throughout dough. Cover and chill for at least 30 minutes for thicker cookies.
07 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
08 - Scoop dough (about 2 tablespoons per cookie) onto prepared baking sheets, spacing 2 inches apart.
09 - Bake for 10–12 minutes until edges are golden brown and centers are just set.
10 - Let cookies cool on baking sheet for 5 minutes, then transfer to wire rack to cool completely.