Heat milk in a large heavy saucepan over medium heat until it begins to bubble around the edges. Meanwhile, whisk together sugar, hot chocolate mix, cornstarch and salt in a large bowl. Whisk in egg yolks.

Slowly add half of the warm milk to the egg mixture, whisking constantly until smooth. Gradually whisk the egg-milk mixture into the remaining hot milk in the saucepan and bring to a boil over medium heat, stirring constantly and scraping the bottom of the pan with a heatproof spatula. Continue cooking, stirring constantly, about 3 to 4 minutes or until the mixture is thickened. Remove saucepan from heat and stir in peppermint extract.

Let pudding cool slightly, stirring every few minutes. Place a piece of plastic wrap directly on the surface of the pudding and refrigerate 4 hours. Meanwhile, place a metal bowl in the freezer at least 30 minutes.

Combine whipping cream, powdered sugar, and vanilla extract in chilled metal bowl. Beat with an electric mixer on medium-high speed until stiff peaks form. 

Spoon pudding evenly into small dessert or plastic cups. Top evenly with whipped cream, and sprinkle with chopped peppermint candies.