Mix all ingredients, except plums, into a smooth curd dough. Chill the dough for about 30 minutes.
With floured hands, wrap the dough around the fruit, form dumplings and boil in simmering water for 10-15 minutes.
For the butter crumbs, heat butter, sprinkle in crumbs and cinnamon, and toast until lightly browned.
Arrange the plum dumplings rolled in butter crumbs and serve.
Preparation Tip:
Sprinkle the plum dumplings with chopped nuts as desired. Instead of the pit, you can put a piece of marzipan in the plum. This will provide a delicious surprise.