TO MAKE CHOCOLATE RIMMED GLASSES
Place cocoa powder on a small plate. Place milk on another plate. Dip top of your glass first in milk to moisten rim then dip in cocoa and turn gently to frost rim with cocoa. Place in refigerator while preparing mousse.
TO MAKE MOUSSE
Place chopped white chocolate in heat proof bowl.
Take 3/4 cup of the heavy cream and heat it just until hot, not boiling, either on stove top or in microwave. Pour hot cream over chopped white chocolate and whisk until smooth. Add peppermint extract and whisk in. Cool completely to room temperature, about 1 hour.
When chocolate mixture has cooled whip remaining cream in a large chilled bowl until it has firm peaks. Fold white chocolate mixture in gently in to combine, fold in chocolate chips as well.
Spoon into prepared chocolate rimmed glasses. Top each glass with a mint chocolate candy and a white truffle. Refrigerate at least 4 hours before serving.