Place cardamom pods, cloves, ginger, and cinnamon stick in the center of a square of cheesecloth or in a coffee filter. Gather up edges and secure with kitchen twine to form a pouch.
Whisk milk, heavy cream, and brown sugar together in a slow cooker. Mix in chopped white chocolate and arrange spice pouch in liquid. Cook white hot chocolate on high 1-1/2 to 2 hours or on low 3 to 3-1/2 hours, stirring hot chocolate occasionally to incorporate white chocolate. Do not allow the liquid to boil. Cook until white chocolate is melted and liquid is steaming.
Once white hot chocolate is completely melted, stir in vanilla extract. Keep white hot chocolate warm in the slow cooker until ready to serve. Remove spice pouch and discard.
Once ready to serve, ladle white hot chocolate into serving mugs and top with whipped cream and a sprinkle of cinnamon if desired. Enjoy!
Notes
Storing InstructionsWhite hot chocolate is best if served warm from the slow cooker.