In a saucepan over medium-high heat, add milk, cinnamon, vanilla extract, and sugar - heat until simmering, but don't let the milk boil.
Lower the heat, add the almond meal and chopped chocolate, and whisk gently until the chocolate is completely melted and blended. Give it a taste to check for sweetness and spiciness.
For a smooth and frothy consistency, blend the mixture with a molinillo, a whisk, or an immersion blender.
Pour the Xocolatl directly into mugs. Serve hot (*scroll up to see my serving suggestions).
Notes
Chop your chocolate finely so that it melts evenly.
If you're using milk chocolate, avoid sugar, as the result will be too sweet.
If your drink is too sweet, add a pinch of salt to cut the sweetness.
Don't substitute ground cinnamon for cinnamon sticks because the drink isn't simmered long enough for the sticks to release their flavor. Use the sticks as garnish and for stirring.
For a quick version, use Mexican chocolate disks, like Ibarra, Abuelita, or Mayordomo.
If you're using chocolate disks, you will only need milk or water - it already contains all the other ingredients - but what's the fun in that?
You don't have to froth Xocolatl, but it's traditionally done using molinillo (*scroll up for directions on how to use it). You can also froth it with an immersion blender, frother wand, or a whisk.
Nutrition information is approximate and meant as a guideline only.
Storage:
Store leftovers refrigerated in an airtight container for up up 4 days.
Reheat in a saucepan over medium heat until steaming but not boiling, or in a microwave.