Beat the egg yolks until they are thick and lemon-colored. Add the sugar a little at a time, beating thoroughly after each addition. Add flavoring (vanilla, brandy or cognac). Beat cream until stiff, and fold in carefully. Add lemon rind and cardamom. Work in flour until dough is smooth. Chill. Roll out dough as thin as possible and cut into diamond shapes with knife or fluted pastry wheel. Make a slit in center of each diamond and pull the tip end of diamond through slit as far as it will go. Drop into hot shortening (350 F). Fry like doughnuts, but only until very lightly browned. They cook almost as fast as they are put into the hot shortening, so they must be turned and taken out quickly. Drain on paper and sprinkle with sugar. Makes about 10 dozen fattigmann.