Heat the milk until lukewarm. Dissolve the yeast in a bowl with the warm milk. Stir in egg, Sugar, salt and cardemom. Add enough flour to make a thick mixture and beat until shiny. Add the rest of the flour to the dough and knead by hand. Leave some of the flour for shaping the buns and continue to work the dough until smooth and elastic. Add the softened fat and knead the dough until it comes off your hands and the edges of the bowl. Cover the bowl with a towel and leave in a warm draught-free place until double in bulk. Then put it on a floured board and shape it into small round buns. Brush the risen buns with beaten egg and sprinkle with Sugar.