In a medium-sized pot, bring the milk to a boil.
Reduce the heat. Sprinkle in cocoa powder, brown sugar, and dark chocolate.
Continue to stir, until all ingredients are melted and combined.
Add the cinnamon, cloves, allspice berries, ginger, and freshly grated nutmeg.
Once cooled, cover the milk and place it in the refrigerator for 1 hour.
When ready to use, strain out the spices and reheat on the stovetop.