01 - Preheat oven to 350°F and line two baking sheets with parchment paper.
02 - In a large bowl, cream together butter, brown sugar, and granulated sugar until light and fluffy.
03 - Beat in eggs one at a time, then add vanilla extract, mixing until combined.
04 - In a separate bowl, whisk together flour, baking powder, baking soda, salt, cinnamon, and nutmeg.
05 - Gradually add dry ingredients to wet, mixing just until combined.
06 - Fold in grated carrots and nuts until evenly distributed.
07 - Scoop 3-tablespoon-sized mounds onto prepared baking sheets, spacing 2 inches apart.
08 - Bake for 12-14 minutes until edges are golden and centers are set. Cool on sheet for 5 minutes, then transfer to wire rack.
09 - Beat cream cheese and butter until smooth. Gradually add powdered sugar, vanilla, and salt, beating until fluffy.
10 - Generously frost each cooled cookie with cream cheese frosting. Garnish with chopped nuts if desired.