Cook the potatoes in their skins. Then drain them and let them steam off briefly.
Melt the butter. Peel the potatoes, press them twice through the potato press and knead them with the butter, egg yolk, starch and salt to a smooth dough. Roll out the dough on a floured work surface for 3 - 4 mm and cut into 12 squares of approx. 9x9 cm.
Brush the edges of the dough with egg yolk and place the chocolate pieces on one side of each square. Fold them up and press the edges firmly together.
To melt the butter, let it brown slightly in a pan. Add breadcrumbs, sugar, poppy seeds, orange and lemon peel and cinnamon, mix well and keep covered warm.
For the sabayon, bring the milk to the boil, then reduce the heat. Coarsely chop the chocolate and let it melt in the hot milk. Whip the egg yolks and sugar with the warm chocolate milk over a hot water bath until a light, frothy cream is formed.
Stir in the chocolate liqueur.
Place the chocolate pouches in plenty of boiling water, reduce the heat and leave the pouches in lightly boiling water for about 5 minutes.
Take the chocolate pouches out of the water, drain well, turn in the warm melt and arrange on plates with the chocolate bayon. Finally dust with icing sugar.