In a saucepan over medium heat, melt the unsalted butter. Continue cooking until the butter turns golden brown and has a nutty aroma—about 5 minutes. Remove it from the heat and allow it to cool slightly.

In a large mixing bowl, combine the brown sugar and granulated sugar. Pour the browned butter over the sugars and mix until well combined.

Beat in the egg and vanilla extract, mixing until the batter is smooth.

In another bowl, whisk together the all-purpose flour, baking soda, and salt. Gradually add this to the wet mixture, stirring until just combined.

Gently fold in the fresh blueberries, being cautious not to mash them.

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

Using a tablespoon or cookie scoop, portion out the dough onto the prepared baking sheet.

Bake for 10-12 minutes or until they turn golden brown.

Let the cookies cool for a few minutes on the baking sheet before transferring them to a wire rack to finish cooling.