1. In a large bowl sift the flour, ginger, cinnamon, cloves, pumpkin spice, baking soda, and salt. Whisk to combine.
2. In the bowl of a stand mixer fitted with the paddle attachment, beat the butter, sugars and molasses until creamy, about 2 minutes.
3. Add in the eggs, one at a time, beating well after each addition Add the molasses and beat until combined.
4. Turn the speed to low and add the dry ingredients and mix until almost incorporated. Cover bowl with plastic wrap and transfer to the refrigerator for 30 minutes to firm up. Scoop the dough into balls using a large cookie scoop (about 60g) each. Return to the fridge for 2 hours or overnight.
5. Preheat the oven to 350 degrees. Line two large baking sheets with parchment paper. Place 8 cookies onto the sheet and lightly press down on the center of each cookie. Bake, one sheet at a time, for 9-10 minutes, or until puffed and lightly golden.
6. Remove pan from oven and allow cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely before frosting.

For the Buttercream

1. In the bowl of a stand mixer, fitted with the paddle attachment, beat the butter for 1 minute, until light and creamy. Stop the mixer and scrape down the sides of the bowl. Add the powdered sugar, followed by the brandy and vanilla. Turn the mixer back to medium high speed and beat for 1 minutes until creamy.
2. Pipe or spread over the cooled cookies.

For the Glaze

1. Sift the powdered sugar into a bowl and make a well in the center for the butter. Warm up the eggnog and pour over the butter to melt it. Add the vanilla and spices and whisk to combine. Spread over the cooled cookies and sprinkle with fresh nutmeg.