Chill the nougat. Warm the milk lukewarm. Crumble yeast into it and dissolve in the milk. Put 200 g flour, sugar, vanillin sugar, 1 pinch of salt, cinnamon, butter and egg into a mixing bowl. Add the yeast milk and knead with the dough hooks of the hand mixer to a smooth dough.
Cover and leave to rise in a warm place for about 50 minutes.
Grease the troughs of a donut baking tray (12 troughs) well. Cut the nougat into small cubes and knead briefly under the yeast dough. With well floured hands, divide the dough into 12 equally sized pieces and press them into the hollows.
Let it go again for about 30 minutes.
Preheat oven (electric cooker: 175 °C/circulating air: 150 °C/gas: level 2). Bake donuts for 18-20 minutes. Allow to cool briefly in the mould, then remove and allow to cool.
Coarsely chop the chocolate coating and melt in a hot water bath. Dip a part of the donuts halfway into the couverture. Place on a cake rack. Let it dry a little, decorate with pearls and let it dry.
Dust the remaining donuts with icing sugar.