In a bowl, combine all the ingredients and knead them. Put in the fridge for 30 minutes. After this time, take pieces of dough and make a flat round shape on your hand. (You can also roll out the dough and cut circles with a glass). Put half a plum and about 1/2 teaspoon of sugar on each circle. Place the second circle of dough on top. Stick with your fingers and form a ball in your hands. Continue this way until the dough is used. I got 10 dumplings from the given amount. Put the dumplings into boiling , slightly salted water and cook around 5 minutes

Melt the butter in a frying pan. Pour breadcrumbs on the melted butter and fry until browned. Add the dumplings to frying pan, coat them propely and fry for 1 minute