Cream butter, sugar, vanilla sugar and 1 pinch of salt. First knead the flour with the dough hooks of the mixer and then knead it with your hands until smooth. Wrap in foil and chill for about 30 minutes.
Line two baking trays with baking paper. Roll out the dough on some flour to a thickness of approx. 1⁄2 cm. Cut approx. 55 rectangles (each approx. 4 x 5 cm) with a dough wheel or knife. Put them on the baking trays. One after the other in a preheated oven (electric cooker: 200 °C/circulating air: 175 °C/gas: see
manufacturer) bake for about 12 minutes.
Roughly chop the sweets. Sprinkle on the hot biscuits and bake for about 3 minutes. Allow to cool for about 1⁄2 minute. If the toffee mixture does not stick completely to the biscuits, press on a little. Let them cool down.
Roughly chop the chocolate coating. Melt in a hot water bath. Let cool for about 20 minutes. Pour into the disposable piping bag and cut off a small corner at the bottom. Decorate the biscuits with chocolate. Leave to dry.