Here is a brief explanation of the Oplatki tradition...
Oplatek, taken from the Latin word oblatum, meaning Sacred Bread, has been the symbol of Christianity and Jesus Christ our bread of life since the Last Supper.
On [Christmas Eve] a festive 12 course meatless dinner is prepared for the gathered family and friends. An extra setting is placed for a beggar (our Lord) who may come to the door, or a poor family (the Holy Family) looking for a place to stay. The host or hostess leads in a special prayer and distributes an oplatek to the participants. Each person breaks off a piece of the other’s oplatek and continues until they have exchanged good wishes and blessings with everyone.
Traditionally at midnight the head of the household takes the pink oplatek and shares it with the animals on his farm or at his home. This custom brings us back to that Holy Night when even animals were able to speak, and to remind us that we are all God’s creatures.
[source - Church Supply Warehouse, http://www.churchsupplywarehouse.com/ ]