1. Make fine crumbs of 2-3 biscuits in a mixie keep aside.
2. Sieve together the dry powder (drinking chocolate, cocoa powder and icing sugar) ingredients twice.
3. Mix the vanilla wafer crumbs in the mixture
4. Beat butter till soft in a bowl.
5. Add sieved mix spoon by spoon to butter and mix well.
6. Beat again till shiny and light.
7. Add essence and mix well. Keep aside.
8. Take milk in a shallow plate.
9. Spread the butter paper sheet in the tray.
10. Sprinkle a little of the chocolate biscuit crumbs all over it.
11. Take six biscuits.
12. Dip one by one in the milk for a few second and place on sheet side by side.
13. They should form a rectangle.
14. Spread a layer of chocolate mixture carefully over the biscuits with a knife.
15. Sprinkle some crumbs over it.
16. Repeat the biscuit, coco, crumbs layers till all the biscuits are used up.
17. Cover the cake on top and sides with remaining.
18. Decorate with either white or chocolate icing as for sponge cakes and glace cherries or strawberries
19. Sprinkle walnuts over it.
20. Chill for 2 hour before serving in the fridge.

Making Time : 1/2 hour (excl setting time)
Shelf Life : 2 weeks (in the fridge)
Serves: 8