In a medium saucepan over medium heat, combine 2 cups of whole milk and 1 cup of heavy whipping cream. Stir gently and heat until steaming, around 3 minutes, but ensure it doesn’t boil.

In a small bowl, whisk together 3 tablespoons of high-quality cocoa powder and 2 tablespoons of grated milk chocolate. Gradually add about ½ cup of the hot milk mixture to this bowl while whisking.

Pour the chocolate mixture back into the saucepan with the remaining hot milk. Lower the heat to medium-low and add 14 ounces of sweetened condensed milk along with ⅛ teaspoon of vanilla extract.

Reduce the heat further and allow the hot chocolate to simmer gently for about 5 minutes. Stir frequently with a spatula.

Ladle the hot chocolate into festive mugs. Top each serving with whipped cream, a sprinkle of ground cinnamon, and optional chocolate shavings.