Wash and drain rice. Combine the rice, cinnamon sticks, and 4 cups of water in a bowl. Soak in the refrigerator overnight or a minimum of 4 hours. (TIP: Break up cinnamon sticks to infuse more flavor.)
Discard the cinnamon sticks (little pieces are ok) and pour the rice and water into a blender. Blend on low for 2-3 minutes until well-blended.
Pour the blended rice mixture through a fine mesh sieve lined with cheesecloth into a large bowl. Repeat straining the liquid two to three times to remove as much gritty bits of rice of rice that you can.
Pour the strained mixture into a pitcher. Add the sweetened condensed milk, evaporated milk, vanilla, and 2-4 cups of additional cold water, to taste. Stir well to combine. Best served cold or with ice. Store horchata in the fridge up to 3-4 days.
Video
Notes
Substitute 2 cinnamon sticks for 2-3 teaspoons of ground cinnamon. (May leave chalky taste.)
Substitute canned milks with 1/2 cup granulated sugar and 2 cups (any) milk. Taste and adjust as desired.
Any raw, uncooked, white rice will work for this recipe; long grain, jasmine, basmati, or short grain.
The flavor is best if the rice soaks for 10-12 hours.
TO MAKE HORCHATA WITHOUT A BLENDER: Skip the blending, and gently pour out the water (leaving the rice on the bottom) or strain the water from the rice without blending it. This will give you the the smoothest Horchata, but you will lose some flavor this way.