Place 1 paper cups in the recesses of each muffin tray (for 12 pieces). Break the dark chocolate into pieces and melt in a hot water bath. Cool down for approx. 5 minutes
Cream butter, 1 pinch of salt, sugar and vanillin sugar. Gradually stir in liquid chocolate coating, then 3 eggs one by one. Mix flour and baking powder, stir in briefly. Spread into the paper cups. Bake in the preheated oven (electric cooker: 175 °C/circulating air: 150 °C/gas: level 2) for 20-25 minutes. Let cool down
Beat 1 egg white, icing sugar and lemon juice in a high mixing bowl with a hand mixer until creamy and shiny. Pour 2 tablespoons of icing into 1 plastic bag. Colour the rest pink with food colouring, spread on the muffins. Let dry for about 5 minutes
Halve the bark chocolate first crosswise and then lengthwise. Place 1 piece in the middle of each muffin. Press 2 biscuits each into the icing as butterfly wings. Cut off 1 small corner from the plastic bag at the bottom. Spray white dots on "wings" and muffins. Let the icing dry