Preheat the oven to 350 degrees. Line two baking sheets with parchment paper and set aside.

Shred your carrots with a box grater or shredding attachment on a food processor. Then, add them to a food processor fitted with an "S" blade. Pulse until they are very fine bits. Measure out ½ cup (75 g) of carrot bits.

Dry your carrots. (This may seem weird but it is the only way these cookies will bake properly and not turn out cakey!) Spread your carrot bits on a plate and place a paper towel over the top. Lightly press to absorb the liquid. Repeat the step at least four more times until hardly any liquid transfers to a paper towel. (It needs to reduce down to just about ⅓ cup (45 g) from ½ cup (75 g). Set aside.

In a small bowl, whisk together the flour, ground spices, baking soda, baking powder and salt. Set aside the dry ingredients.

In a large bowl cream the butter and brown sugar together with an electric mixer on high speed until pale in color and fluffy, 2-3 mins.

Add in the egg yolks and vanilla and mix on medium speed then medium-high speed until pale and fluffy, about 1-2 minutes. Scrape down the sides of the bowl as necessary.

Add in the dried carrot bits and combine on low speed just until combined.

Add the flour mixture to the wet ingredients and mix on low then medium speed until combined.

Scoop the dough onto the prepared baking sheets, using a medium sized cookie scoop, about 2 tbsp of dough per scoop. Scoop 6 cookie dough balls per baking sheet. (You should be able to get 18 cookies.)

Bake the cookies for 11-13 minutes. (12 minutes is usually perfect.) Let them cool for 5 minutes on the cookie sheet, then transfer them to a wire rack to finish cooling.(When the cookies are straight out of the oven, scoot a circular cookie cutter around their edges to give them a perfect circular shape.)

Add the butter to a medium sized bowl. Whip with an electric mixer on high speed until pale in color, fluffy and about double in size, about 5 minutes.

Add in the cream cheese and mix on medium-high speed until thoroughly combined.

Sift in the powdered sugar and mix on low then medium speed until combined. Then, mix on high speed until light and flufy, about 1 more minute.

One the cookies are completely cooled, spread cream cheese frosting onto each using a mini offset spatula.

Sprinkle with chopped walnuts if you desire, then serve!