In a small saucepan, heat the milk over medium heat until steaming, but not boiling.
In a separate bowl, whisk together cocoa powder, sugar, and salt.
Add a few tablespoons of the warm milk to the cocoa mixture to create a smooth paste.
Pour the paste back into the saucepan with the remaining milk.
Stir continuously until the mixture is well combined and heated through.
Add vanilla extract and stir well.
If desired, add a dash of cinnamon or nutmeg for extra flavor.
Remove from heat and pour into mugs.
Top with whipped cream, chocolate shavings, or a sprinkle of cocoa powder.
Serve immediately and enjoy your homemade hot chocolate!