Quickly knead curd, flour and margarine into a smooth dough. Chill for 1 hour. Roll out dough to thickness of back of knife, cut into 2.5 x 2.5 cm squares. Place a dot of jam in the center of each, brush the edges with egg, fold corners over each other and press edges down. Bake in the preheated oven at 200 °C for about 15 minutes until golden brown. Allow to cool slightly and sprinkle with powdered sugar and cinnamon mixture while still warm.