01 - In a medium bowl, whisk together flour, baking soda, baking powder, ground ginger, cinnamon, cloves, nutmeg, and salt until evenly combined.
02 - In a large bowl, beat the softened unsalted butter and dark brown sugar with an electric mixer on medium speed until light and fluffy, about 2 minutes.
03 - Add the egg, unsulphured molasses, and vanilla extract to the butter-sugar mixture. Mix until fully combined.
04 - Gradually add the dry ingredient mixture to the wet ingredients, mixing until a soft and uniform dough forms.
05 - Divide the dough into two portions, flatten into disks, wrap each in plastic wrap, and refrigerate for at least 1 hour to firm up.
06 - Preheat oven to 350°F (175°C). Line baking sheets with parchment paper.
07 - On a lightly floured surface, roll one disk of dough at a time to a 1/4-inch thickness.
08 - Use a gingerbread men cookie cutter to create shapes, placing them about 1 inch apart on prepared baking sheets.
09 - Bake in the preheated oven for 8 to 10 minutes, until the edges are set. Cool on baking sheets for 5 minutes before transferring to a wire rack to cool completely.
10 - Whisk powdered sugar with 1 to 2 tablespoons milk (and egg white if using) until smooth and pipeable. If desired, color a portion with black food coloring gel for detail work.
11 - Fill a piping bag fitted with a small round tip with white icing. Pipe skeleton bones onto fully cooled cookies. Use black icing for additional detailing as desired.
12 - Allow decorated cookies to dry completely before serving or storing. Store in an airtight container for up to 5 days.