Rinse the rice under cold water until the water runs clear.

In a bowl, combine the rinsed rice with 2 cups of water. Soak for at least 4 hours or overnight.

In the blender, add the soaked rice and soaking water and blend on high until smooth, about 1-2 minutes.

Strain the blended mixture through a fine mesh strainer or cheesecloth into a large bowl.

Add the remaining water, sugar, cinnamon, milk, and vanilla extract to the strained liquid and stir until the sugar dissolves.

Refrigerate the horchata for at least 1 hour to allow the flavors to meld.

Once chilled, stir the horchata well, pour into glasses over ice, and sprinkle with additional cinnamon if desired.

Enjoy the refreshing, creamy horchata.