Start by placing the chocolate and 60 ml double cream into a bowl and melt together. Whip the remaining cream to stiff peaks then whisk in the cream cheese and icing sugar till smooth. Next, fold in the melted chocolate mixture till smooth followed by the coffee if using. Spoon or pipe the chocolate mousse into small jars or terracotta pots and top with the crumbled chocolate muffin to look like soil. Finish off by sticking the small sugar carrots on the top and chill before serving.