Mix the flour, salt, cocoa powder and vanilla in a bowl. Add the butter and rub together using your hands to form an even, crumbly mixture. Mix in the almonds, icing sugar and chocolate. Add the egg, mix quickly to form a dough (do not knead), cover and chill for approx. 30 mins.
On a lightly floured surface, shape the dough into rolls the width of your finger, cut into pieces approx. 2 cm long. Roll up the pieces of dough, shape into crescents, transfer to three baking trays lined with baking paper, chill for approx. 30 mins.
Approx. 15 mins. per tray in the centre of an oven preheated to 180°C. Allow the crescents to cool slightly on the tray, leave to cool completely on a cooling rack. Drizzle the cake icing over the top to create a lattice effect.