01 - Place butter in a medium saucepan over medium heat. Cook, stirring constantly, until butter foams, turns golden brown, and releases a nutty aroma, approximately 4–6 minutes. Immediately transfer to a large mixing bowl and cool for 10 minutes.
02 - Add brown sugar and granulated sugar to the cooled brown butter. Whisk vigorously until fully combined and smooth. Stir in eggs one at a time, followed by vanilla extract, mixing until uniform.
03 - In a separate bowl, whisk together flour, baking soda, baking powder, salt, cinnamon, nutmeg, and ginger until evenly distributed.
04 - Add dry ingredients to the wet mixture. Stir gently until just combined—do not overmix. Fold in oats, grated carrots, nuts, and raisins if using.
05 - Cover bowl and refrigerate dough for 30 minutes. This step enhances chewiness and flavor development, though not strictly required.
06 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
07 - Scoop chilled dough into 2-tablespoon balls, arranging them 2 inches apart on prepared baking sheets.
08 - Bake for 11–13 minutes, until edges are set but centers appear slightly underbaked. This ensures a chewy texture.
09 - Let cookies rest on baking sheets for 5 minutes, then transfer to wire rack to cool completely.
10 - Beat softened cream cheese and butter until creamy. Gradually incorporate powdered sugar and vanilla, beating until smooth. Drizzle over cooled cookies if desired.