In a medium saucepan, melt the unsalted butter over medium heat, stirring constantly until it turns golden brown and develops a nutty aroma.

Remove it from heat and let it cool slightly. In a large mixing bowl, combine brown sugar and granulated sugar with the browned butter, whisking until smooth.

Add the two large eggs one at a time to the sugar mixture, whisking vigorously until glossy.

In a separate bowl, whisk together all-purpose flour, baking soda, ground cinnamon, and salt. Gradually add to the wet ingredients, stirring gently.

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

Preheat your oven to 350°F (175°C) and line baking sheets with parchment paper. Scoop dough onto prepared sheets and bake for 12 minutes.

Allow cookies to cool on the baking sheet for a few minutes before transferring to a wire rack to cool completely.