Use a coffee/spice grinder to break up the rice. Add the pulverized rice, 5 cups of water and cinnamon sticks to a large measuring cup or glass bowl. The other option is to put both the rice and water into a high speed blender and blend until the rice breaks up. Add the cinnamon sticks to the rice/water mixture. Let the rice/water mixture stand at room temperature for 3 hours minimum. You can store it in the refrigerator overnight to soak longer.

Using a fine mesh strainer, strain the rice water into a pitcher. Discard the rice and cinnamon sticks. Stir in the vanilla extract, maple syrup, ground cinnamon and almond milk, if using. Chill before serving. Serve over ice with a sprinkle of ground cinnamon.