Add whole milk, heavy cream, orange zest, and cinnamon sticks to a medium pot over medium heat. Heat until just simmering, stirring occasionally.
Take pot off heat, cover with lid or plastic wrap, and let infuse for 30 minutes.
Using a slotted spoon or strainer, remove orange zest and cinnamon sticks. Place the pot back onto medium heat until warm.
Whisk in melted chocolate and then light brown sugar and salt. Optional: Whisk in peppermint extract and/or Baileys Irish Cream.
Serve immediately in a cozy mug topped with whipped cream, marshmallows, and/or a peppermint stick. Enjoy!