Wrap the dough in plastic cling film. Chill for 30 minutes.
Preheat oven to 350F.
Roll out dough on a lightly floured surface.
Using the Linzer cutter* (without the insert), cut approximately 20 shapes for the backs or bottoms of the cookie.
Insert the cutout shape into the cookie cutter and cut out several. Switch and repeat using the insert shapes you like.
Bake for 10-12 minutes.
Remove from oven and transfer to wire rack to cool completely.
Make the Chocolate Ganache Filling:
Place chopped chocolate in a heat-safe bowl.
Heat cream until it boils.
Remove from heat and pour over the chocolate, whisking until it melts.
Add cinnamon and blend thoroughly
Assemble the Cookies
Using a small spatula or butter knife, spread a thin layer of ganache on the bottom part of the cookie.
In a small bowl, using a small fork or a tiny whisk, mix the glitter dust into the powdered sugar a little at a time until the sugar is tinted.
Dip each cookie half into the tinted sugar. Shake off the excess and pair up a solid bottom half with a cutout top.
Plate and serve.
Recipe Notes
* If you don't have inserts, you can use a fluted or plain round cutter and cut all your cookies at once and then use a small cookie cutter, round, heart, etc. to cut out the remaining cookie halves with inserts.