Coarsely chop the dark chocolate. Melt butter and chocolate in a saucepan over low heat while stirring, remove from the heat and pour into a mixing bowl. Add 225 g sugar, vanillin sugar, salt, eggs, flour and baking powder. Mix to a smooth dough with the whisks of the hand mixer. Place paper baking cups in the hollows of a muffin tray (12 hollows).
Pour in the dough and bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 20 minutes. Remove the muffins from the oven and let them cool down on a cake rack. Approx. 30 minutes before serving, beat egg whites and 150 g sugar until stiff and the sugar has dissolved. Spoon the beaten egg whites onto the muffins and bake in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 5-8 minutes until the meringue takes on colour. Dust with icing sugar before serving
45 minutes waiting time