Use a rolling pin to mash the candied ginger into a paste.
Use a sharp knife to slice the vanilla bean lengthwise. Separate the seeds from the outside skin by scraping the blade of the knife along the inside of the bean. Place the vanilla bean seeds, butter, sugar, egg yolks, and ginger in a medium-size mixing bowl and beat with an electric mixer on low speed until the ingredients are combined, about 1 minute. Combine the baking powder, salt, cocoa powder and flour and add to the butter mixture all at once. Beat on low speed just until combined, about 1 minute. Do not overmix the dough or it will become tough. Remove the dough from the bowl.
Preheat the oven to 400 degrees F.
I baked my cookies in a special flexible baking sheet with dome-shaped cavities. Roll the dough into a rope that is about the same diameter as the cookie mold. Use a knife to cut each piece of dough. Press the dough into the mold. Repeat until all of the cavities are filled. Bake 15 to 20 minutes.
To make the chocolate fans: Use an offset spatula to spread a very thin layer of tempered chocolate onto a piece of marble. Use a spatula to clean away chocolate so you are left with a rectangle shape. Let the chocolate set slightly. Place 1 hand on the handle of the cake triangle and rest your thumb on the blade of the triangle. Push the triangle through the chocolate in strips of about 2 inches. Use your thumb to catch 1 side of the chocolate to create small chocolate fans. Pinch the short side to create the handle of the fan. I colored my fans with my airbrush but you could also use a paintbrush. If using an airbrush, place a few drops of color in the airbrush.
If using a paintbrush, mix together a few tablespoons of the cocoa butter with a small amount of powdered food color. It will be easier if you use yogurt machine to store and warm your paints. Apply color where you are inspired to do so.
When the cookies have cooled, use a sharp knife to cut a wedge from the top of each cookie. Position the chocolate fans on top of each cookie.
Source: Flexible baking pans – any kitchen supply store