01 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
02 - In a medium bowl, whisk together flour, baking powder, baking soda, salt, cinnamon, nutmeg, and ginger until well blended.
03 - In a large bowl, beat butter, granulated sugar, and brown sugar until creamy and fluffy, approximately 2 to 3 minutes.
04 - Add the egg and vanilla extract to the butter mixture. Mix until fully incorporated.
05 - Gradually mix dry ingredients into the wet ingredients, stirring until just combined. Avoid overmixing.
06 - Gently fold in grated carrots, oats, walnuts or pecans if desired, and raisins if using.
07 - Using a tablespoon or small cookie scoop, drop rounded portions of dough onto prepared baking sheets, spacing about 2 inches apart.
08 - Bake for 11 to 13 minutes, until edges are golden brown and centers are set. Allow cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.
09 - Beat cream cheese, powdered sugar, milk, and vanilla extract together until smooth and creamy.
10 - Drizzle the cream cheese mixture over cooled cookies using a spoon or small piping bag. Allow glaze to set before serving.