Soak the rice with a cinnamon stick for as long as you think necessary (until the rice is very soft). I left it for 6 hours.

After the rice has soaked, dissolve the cup of sugar in 6 liters of water in a container (the recipe I saw used two cups, but I find that too sweet).

Blend half of the rice very well with 1/2 cup of water, the cinnamon, and the evaporated milk, then strain it well.

Blend the remaining rice, adding the sweetened condensed milk and the Abuelita chocolate tablet (microwave for 30 seconds until it softens) and vanilla extract to taste. I used two and a half caps from the vanilla bottle. Then blend everything and strain it again.

Serve with plenty of ice, and adding ground cinnamon is optional.