Line a 2lb loaf tin with cling film, lay 8 or 9 sponge fingers. Make a mug of strong coffee and allow to cool. Pour half the coffee over the finger in the loaf tin and the other half over 8 or 9 more fingers on a plate. Mix quark and fromage frais with vanilla essecence and swwetener to taste and use 1/3 over the fingers then add the fingers on plate and layer with another 1/3 of mixture cover with cling film and keep final 1/3 mixture until ready to serve. Put all in fridge for at least 1 hour. turn out and spred with final 1/3 of mixture