Blanch the almonds by tossing them into boiling water for about a minute, then draining under cold water. After blanching, give each of those little guys a squeeze and the skins should slip right off. Dry the almonds off with a paper towel, then toast them in a dry skillet over medium heat until lightly brown.
Pulverize the rice in a spice grinder or blender. You can use a coffee grinder, but make sure it's very clean and even then you may get some coffee flavor in your horchata. Grind to a fine powder.
Add the ground rice to a large jar or bowl with the almonds and a cinnamon stick. Stir in the 3 cups of hot water, allow to cool to room temperature then cover and let stand overnight (not in the fridge!).
The next day:
Transfer the mixture into your blender and add the 2 cups of cold water. Blend until it's nice and smooth (about 1 - 4 minutes depending on your blender).
Strain the blended mixture slowly into a pitcher using a few layers of cheesecloth or a tea strainer and discard the stuff that doesn't pass through easily.
Dissolve the sugar in the 1/3 cup of water either on the stove or in the microwave. Taste it to see if it's sweet enough for your liking and add more sugar if needed.
Refrigerate then serve over ice. Garnish with cinnamon or a cinnamon stick.
