In a medium saucepan, melt the butter over medium heat, stirring continuously until golden brown and nutty, about 5-7 minutes. Allow to cool slightly.

In a large bowl, combine brown sugar and granulated sugar. Pour in browned butter and mix until well combined.

Stir in egg and vanilla extract, mixing until smooth.

In another bowl, whisk together flour, baking soda, and salt. Gradually add to wet ingredients, stirring until just combined. Fold in chopped pecans.

Cover the bowl with plastic wrap and chill the dough in the refrigerator for 30 minutes.

Preheat oven to 350°F (175°C) and line a baking sheet with parchment paper.

Scoop out portions of dough onto the prepared baking sheet.

Bake for 10-12 minutes, until edges are golden brown but centers look slightly underbaked.

Allow cookies to cool on the baking sheet for 5 minutes before transferring to wire rack.