Chop the chocolate and melt it over a warm water bath. Pour into a small piping bag. Spray 4 glasses (200 ml each) on the inner glass wall with it, chill. Chop the chocolate coating. Heat the milk, dissolve the chocolate coating and espresso powder in it and let it cool down. Whip 200 g cream until stiff.
Stir the quark and 1 packet of vanillin sugar into the chocolate milk. Fold in the cream and fill into the glasses. Chill for 1-2 hours. Whip 100 g cream until stiff, pour in 1 sachet of vanillin sugar. Pour into the glasses. Sprinkle with chocolate shavings