For the syrup, combine all the ingredients in a small saucepan, mix well, and bring to a light boil over medium heat. Turn the mixture down to low-medium heat and let it simmer for 15 minutes. It should thicken over time and become like a maple syrup consistency.

When the syrup is done, warm the milk over low heat and add in the sugar, cocoa powder, and syrup. Pour into a mug and top with marshmallows or whipped cream if desired. Refrigerate any leftover syrup in an airtight container.