Xocolatl (Aztec Chocolate Beverage)

Steps

1. Toast cornmeal in dry skillet over medium-high heat, stirring frequently. When cornmeal turns a dark tan or light brown color, add 470 ml water, stir, and remove from heat. Let cornmeal soak in water overnight.
2. Grind cornmeal in blender until it forms a smooth paste. Filter or strain the paste to remove the coarse corn mush. The goal is to make a smooth but thick gel to be used as an emulsifier and thickener. It may be possible to substitute something made of cornstarch instead. Discard the mush and set aside the strained gel.
3. Bring 470 ml of water to a boil in a saucepan. Meanwhile, cut open the chili peppers and remove the seeds. Add the peppers to the boiling water and boil them until the amount of liquid is reduced to 240 ml. The liquid should be pale yellow and taste very spicy. Discard peppers and set aside liquid.
4. Add chocolate and 240 ml water to saucepan. Stir frequently over medium heat until chocolate is melted. Slowly add cornmeal gel (you might want to decant it so that any settled lumps or grit remain at the bottom). Add vanilla, spices, and sweetener if desired. Slowly add pepper liquid until the desired spiciness is reached.
5. Transfer mixture to blender, add lots of ice cubes, and blend until smooth and frothy.