Prepare cookie doughs as directed. Use flour-coated circle cutters to cut out circles from sugar cookie dough, and use cocoa-coated cat cutters to cut out cats from black cocoa cookie dough. Bake as directed and let cool completely. Use royal icing to decorate sugar cookies and attach cat cookies on top.  Mix a small amount of clear alcohol with silver luster dust and use a paint brush to paint small brushstrokes on the royal icing of the sugar cookies. Repeat with black luster dust to paint bats.