In a large bowl mix 2 cups icing sugar, flour and salt. Make a well in the centre and set aside.
In another bowl combine melted butter and vanilla scrapings. Pour vanilla butter, egg whites and 1 tablespoon cream into well of dry ingredients. Mix until smooth. Fold in 45g grated chocolate. Chill in refrigerator 2 hours or overnight.
Preheat oven to 200 degrees C. Line a baking tray with waxed paper.
Make 10cm wide circles of batter on the baking tray. One way to do this is to cut a stencil out of cardboard, lay it down on the tray and place 2 teaspoons of batter inside the circle. Make 3 circles on a baking tray.
Bake in preheated oven 2 minutes, rotate pan and bake 2 minutes more until golden. Working quickly, remove biscuit from tray with a spatula and roll around the handle of a wooden spoon. Place rolled biscuits on wire rack to cool completely. If biscuits harden before rolling, return to oven for 30 seconds to soften. Repeat to use all remaining batter.
To make coffee cream: Beat together coffee liqueur and instant coffee until powder is dissolved. Beat in 2 1/2 cups cream and 1/4 cup icing sugar until soft peaks form. Refrigerate 15 minutes.
Fill cooled biscuits with coffee cream using a pastry bag. Dip each end of filled biscuits in grated chocolate. Serve at once, or store in an airtight container up to 3 days.