Heat over medium heat until the milk becomes hot and small bubbles begin forming around the edges.

Add the chopped chocolate, cocoa powder, brown sugar, vanilla extract, and salt.

Whisk continuously until the chocolate melts completely and the mixture looks smooth and glossy.

In a small bowl, whisk the cornstarch with the remaining 1/2 cup milk until completely dissolved and lump-free.

Slowly pour the cornstarch mixture into the saucepan while whisking constantly.

Continue cooking over medium-low heat, stirring frequently as the drink begins to thicken.

Simmer gently for several minutes until the texture becomes silky and lightly creamy.

Remove the cinnamon stick once the flavor has infused into the drink.

Taste and adjust sweetness if desired.

Strain if a smoother texture is preferred.

Pour into mugs and serve immediately while hot.