Cream together the ICBINB with the sugar till soft and light. Mix in the egg yolk and vanilla extract. Fold in the flour and baking powder, followed by the chopped pistachios and cranberries. Form into a sausage, wrap in cling film and chill in the fridge for 2 hours. When ready to cook, remove from the fridge and discard the cling film. Cut into ½ inch thick slices and place onto baking sheets lined with baking paper spaced well apart. Bake at 200`c for approximately 20 minutes or until golden around the edges. Cool down completely before sandwiching the cookies together with the ice-cream and half dipping in melted chocolate. Place into the freezer to harden up before serving.