01 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
02 - In a large bowl, beat softened butter, brown sugar, and granulated sugar until light and fluffy using electric mixer.
03 - Beat in eggs one at a time until fully incorporated. Add vanilla extract and mix until combined.
04 - In a separate bowl, whisk together flour, baking powder, baking soda, salt, cinnamon, and nutmeg until well blended.
05 - Gradually add dry ingredients to wet mixture, mixing just until combined. Do not overmix.
06 - Gently fold grated carrots and chopped nuts (if using) into dough until evenly distributed.
07 - Scoop 3-tablespoon portions of dough onto prepared baking sheets, spacing at least 2 inches apart.
08 - Bake for 12 to 14 minutes until edges are golden brown and centers are set. Cool on baking sheet for 5 minutes before transferring to wire rack.
09 - Beat cream cheese and softened butter until smooth and creamy. Gradually add powdered sugar, vanilla, and salt. Continue beating until fluffy and well combined.
10 - Once cookies are completely cool, generously frost each cookie with cream cheese frosting. Garnish with chopped nuts if desired.