In a saucepan, heat the milk over medium heat until steaming but not boiling.
Whisk in the cocoa powder and sugar until smooth.
Add chocolate chips if using, stirring until melted and well combined.
Stir in vanilla extract and a pinch of salt for enhanced flavor.
Remove from heat and pour into mugs.
Top with whipped cream or marshmallows as desired.
Sprinkle extra cocoa powder or cinnamon on top for garnish.
Serve immediately while hot.
Adjust sweetness by adding more sugar if needed.
Experiment with flavored syrups for a unique twist!