Break chocolate into pieces. Melt 25 g chocolate and oil while stirring. Pour on a piece of baking paper and spread thinly with a pallet or a large knife. Crush the coffee beans and sprinkle on the chocolate.
Let it set.
Carefully heat the milk and 175 g of chocolate and melt the chocolate. Let it cool down for about 15 minutes. Whip the cream until stiff and fold it into the liquid chocolate. Pour cream into 4 glasses and chill for about 1 hour.
Cut the mocha chocolate into narrow strips. Peel off the baking paper and decorate the chocolate cream with it.