In large olla or saucepan, combine 8 cups (2 L) of water, the cinnamon stick, and piloncillo. Stir to combine, cover and bring to a boil.
Once the piloncillo has dissolved and the water is boiling, add the ground coffee and remove from the heat.
Strain the coffee through a double-mesh strainer to serve or allow for the coffee grounds to sink to the bottom of the pot.
Add a splash of milk if you like or enjoy just as is.