ice skate-shaped cookie cutter, large offset spatula, 4 piping bags, #1 tip, #4 tip, two #2 tips, toothpicks, 2 paintbrushes
Position a rack in the center of the oven and preheat the oven to 350 degrees F. Line a baking sheet with parchment paper.
Dust a work surface with a light coating of flour and roll out the dough to a thickness of about 1/4 inch. Use an ice-skate cookie cutter to cut out cookies. Use an offset spatula to carefully transfer cookies to the prepared baking sheet, leaving about 1 inch of space between each cookie.
Bake until the cookies are golden brown round the edges, about 10 minutes. Let cool for a few minutes on the cookie sheet to firm up, then transfer to a cooling rack to cool completely.
Meanwhile, fill a piping bag with a #4 tip with the white icing, a piping bag with a #2 tip with the black icing, a piping bag with a #2 with the gray icing, and a piping bag with a #1 tip with the blue icing.
Start with the white royal icing bag; this icing will double as your outline and flooding icing. On a cooled cookie, outline where the tongue of the ice skate will be, bringing the line down to the top of the tip of the shoe. Fill it in and even out the shape using a toothpick. Repeat with the remaining cookies.
Next use the black royal icing bag; this will also double as your outline and flooding icing. Pipe a thin sole on a skate and then pipe a heel; flood and use a toothpick to make everything even. Repeat with the remaining cookies.
Use the gray icing to outline the blade of a skate. Use a toothpick to get the sharper points and straight lines. Repeat with the remaining cookies.
Outline the rest of the skate boot with the white royal icing and flood the outline. Use your toothpick to smooth out the icing and eliminate any air bubbles. Repeat with the remaining cookies.
Immediately use your gray icing to pipe 6 evenly spaced lace holes on a cookie. Starting at the cookie edge, use the blue icing to make lace strands: Above the 6 lace holes, make two sets of two laces that connect evenly with the previous lace holes. (They will make a > sign). Repeat with the remaining cookies. Let cookies dry for about 15 minutes.
Mix the pearl dust with enough grain alcohol to make a thin paste. Use a paintbrush to paint the paste onto the blade of a skate. Use the same pearl dust on a dry paintbrush to highlight the boot of the cookie by lightly brushing it with pearl dust. Repeat on the remaining cookies. Allow cookies to dry for about an hour before serving.