01 - Combine whole milk and heavy cream in a medium saucepan over medium heat. Warm until steaming but not boiling.
02 - Whisk in cocoa powder, semisweet chocolate chips, granulated sugar, and salt. Continue whisking until chocolate and sugar fully dissolve and mixture is smooth and hot, about 3 to 5 minutes.
03 - Remove saucepan from heat. Stir in peppermint and vanilla extracts evenly.
04 - Ladle hot cocoa into serving mugs. Generously top with mini marshmallows and, if desired, sprinkle crushed peppermint candies over the top.
05 - Serve immediately to enjoy the beverage at its warmest.