In a medium bowl, whisk together the flour, dark cocoa, baking powder and salt. Set aside.
Next, in a large bowl, beat the butter, sugar and brown sugar with an electric mixer on medium until light and fluffy. Add the egg, vanilla and food coloring gel. Beat to incorporate. With the mixer on low, gradually add the dry ingredients just until combined. Remove to the clean counter and knead a few times. It should be like Play-Doh.
Divide dough in half. Wrap in plastic wrap and shape into a disk. Place the two wrapped dough disks in the refrigerator for 20-30 minutes. Preheat oven to 350°F. Roll one disk of dough between two sheets of parchment paper until it's 1/8" thick. Remove top sheet of parchment. Cut dough into gingerbread men. Remove excess dough, then slide the whole sheet onto a rimmed baking sheet.
Bake for 10 minutes. Remove from oven and let cool in pan for 20 minutes. Using a flat or offset spatula, transfer to a cooling rack to cool completely. Repeat cutting and baking process with remaining dough.
For the icing
Whisk together the meringue powder and powdered sugar and water. Keep whisking until thoroughly combined. Transfer icing to a piping bag fitted with a small round tip (such as #3) and draw on some bones.
Notes
Store cookies in an airtight container at room temperature. These cookies will keep in a covered container for up to 5 days.