Put the milk with the coarsely grated couverture in a saucepan. Halve the vanilla pod, scrape out the pulp. Add the vanilla pulp and the vanilla pod to the milk. Now mash the peppercorns, mix them with the milk and bring the whole thing to a boil over a moderate heat. Take off the stove and let it steep for a moment.
Pass the chocolate through a sieve. Add the cocoa powder and brown sugar and stir until the sugar has dissolved.
Pour the vanilla chocolate into decorative cups. Place a vanilla stick in each of the cups, garnish the drink with chocolate biscuits and serve immediately.