Note: this cookie dough requires at least 2 hours of chilling, or overnight. Colder cookies won't spread in the oven and will keep their snowflake shape.
In a medium bowl, whisk together the flour, baking soda, salt, cinnamon, ginger, nutmeg, all spice and cloves and set aside.
In the bowl of a stand mixer (or a large bowl if using a hand mixer), beat butter and brown sugar together using the paddle attachment for 2-3 minutes. Do not skip this step. Add the molasses, egg, and vanilla and beat again for 1-2 minutes.
Scrape down the sides of the bowl then add half of the dry ingredients and beat until combined. Add the second half of the dry ingredients and mix again on low until combined and the dough starts pulling away from the sides of the bowl.
Separate the dough into two equal pieces then dump one half out onto a floured a large piece of plastic wrap. Gently press the dough out into a large disk shape and wrap it completely with plastic wrap. Repeat the process with the other half of the dough then place both halves in the fridge to chill for at least 2 hours or up to 3 days. The longer it chills the thicker it will be. You cannot skip this step or the cookies will spread. You can also freeze the dough at this point. See notes for freezer instructions.
When you’re ready to bake the dough, preheat the oven to 350°F. Remove one half of the dough from the oven and dump it out onto a floured surface. Flour your hands and the rolling pin then roll the dough out to 1/4 inch thickness.
Cut out the dough into snowflake shapes and place 1-2 inches apart on a large baking sheet lined with parchment paper.
When there isn’t anymore room to cut out cookies from the dough, roll it back up into a ball and re-roll it out to 1/4 inch thickness. Repeat the process until all the dough is gone. Repeat the process with the other half of the dough.
Bake in the preheat oven for 9-11 minutes, until just set and the bottom edges of the cookies turn a light golden brown. Allow them to cool on the baking sheet for 5 minutes then transfer the cookies to a wire rack to cool completely before icing.