A special sweet Christmas treat is called Dominostein or Dominosteine (Plural).
Der Stein“ is a stone. So it is a domino stone.

The size is about 2 cubic centimeters. The three levels that you see in the picture are:
bottom: ginger bread, middle: fruit jelly, top: marzipan.
Hmmmmm….. lecker!  (Yummie)
Sehr typisch für Weihnachten!  (Very typical for Christmas!)
Dominosteine!