01 - In a small saucepan over medium heat, combine milk, chopped chocolate, cocoa powder, sugar, cinnamon, nutmeg, cayenne pepper if using, and salt.
02 - Whisk continuously until the chocolate melts and the mixture becomes smooth and steaming, about 5 to 7 minutes. Avoid boiling.
03 - Remove the saucepan from heat and stir in vanilla extract.
04 - In a chilled bowl, whip heavy cream, powdered sugar, and vanilla extract together until soft peaks form.
05 - Pour hot chocolate into mugs.
06 - Generously add the whipped cream on top of each mug.
07 - Sprinkle ground cinnamon or chocolate shavings on top as desired.
08 - Enjoy the beverage while warm.