01 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
02 - In a medium bowl, whisk together flour, cinnamon, ginger, nutmeg, baking soda, baking powder, and salt until well blended.
03 - In a large bowl, beat softened butter, brown sugar, and granulated sugar until light and fluffy, approximately 2-3 minutes.
04 - Beat in the egg and vanilla extract until fully incorporated.
05 - Stir in grated carrots until evenly distributed throughout the batter.
06 - Gradually add the dry ingredients to the wet mixture, mixing until just combined. Avoid overmixing to prevent tough cookies.
07 - Fold in oats, walnuts or pecans, and raisins until evenly distributed.
08 - Drop tablespoon-sized mounds of dough onto prepared baking sheets, spacing 2 inches apart to allow for spreading.
09 - Bake for 11-13 minutes until edges are golden brown and centers are set. Cool on baking sheet for 5 minutes, then transfer to wire rack to cool completely.
10 - Beat cream cheese and softened butter together until smooth and creamy. Add powdered sugar, vanilla, and salt; continue beating until fluffy and well combined.
11 - Once cookies have cooled completely, spread or pipe frosting onto each cookie. Serve immediately or store refrigerated.