1. In a small bowl combine the flour, spices and salt. Set aside.
2. In the bowl of a stand mixer fitted with the paddle attachment beat together the butter and sugars until light and fluffy- about 3 minutes.
3. Add the egg yolk, sourdough discard and vanilla and continue to mix until well combined.
4. Add the flour, spices and salt. Mix on low speed, until the dough starts coming together. Don’t over mix.
5. Divide the dough in half and shape into two discs. Place one between two pieces of parchment paper and roll out to 1/4 inch thickness. Repeat. Place the sheets on a cookie sheet and transfer to the fridge for a minimum of 2 hours, or up to 48 hours. Or place in the freezer for at least 30 minutes. (I recommend making the carrot ganache here!)
6. Preheat the oven to 350. Line two baking sheets with parchment paper.
7. Remove dough from the fridge/freezer and peel off the parchment paper. Using a cookie or biscuit cutter, cut out desired shapes Using a smaller cookie cutter, cut out the middles of half of the cookies. Re roll the scraps and place in the freezer to firm up.
8. Place the cut-outs on your cookie sheets, about 1-2 inches apart. Bake for 8-12 minutes, or  until the edges are light golden brown. Let cool on the pan for 5 minutes. Transfer to a wire rack, let cool completely. Repeat with the remaining dough.
9. Dust the tops of the cookies with powdered sugar. Add a spoonful of ganache to the bottom halves. Place the sugared cookies on top pressing gently to create a cookie sandwich.

Make the Ganache

1. Place the chocolate into a heat proof bowl. Add the cream and carrot juice to a small sauce pan and bring up to a bare simmer. Pour the cream over the chocolate and let sit for a minute. Stir until the chocolate is melted and the ganache is creamy. Transfer to the fridge, it will continue to thicken.