In a bowl, combine the rice, hot water, and the cinnamon sticks. Refrigerate for at least 5 hours, or overnight for even better results.
Blend the soaked rice and cinnamon mixture until smooth. Strain the mixture through a fine mesh sieve or cheesecloth into a pitcher, discarding any solids.
Add the condensed milk, evaporated milk, 2 cups of water, and vanilla extract (if using). Stir until fully combined.
Pour the horchata over ice and garnish with a sprinkle of ground cinnamon.
This recipe is perfect for 3 servings.
If you enjoyed this small batch horchata recipe, you might also like this strawberry agua fresca recipe.