OK, so I looked online and saw tons of recipes which impled that, like Goulash, means you can vary the recipe widely and have the same general result.
My attempt was not so good.
Horchata is a Mexican rice-based drink which is a great summer cooler. It can be thick and taste like rice pudding, or thin and almost be like having a cinnamon vanilla cooler.
First, I didn't have any long-grain rice so I used some Japanese sushi rice.
Then I tried to grind it into flour, using first a blade grinder and then a mini-chop. But I had rinsed the rice first, so I got a wet semi-paste of rice nuggets and glue.
I didn't have any blanched almonds, so 1/4 cup of roasted almonds coarsely ground.
Cinnamon sticks were OK. I let the mixture sit with a couple cups of water overnight, then blended.
The directions say to strain thru cheesecloth, which I didn't have. So first I tried a coffee filter, which went so slowly that I only got a few drops in a few minutes. So I changed to a typical sieve, which of course filtered only the larger pieces but let almost everything go through.
A couple of blenderizing and sieve-ing and sweetening later, the result was a chalky, powdery, over-cinnamony, horchata-like drink which had few of the qualities that we enjoyed on our recent trip to Tucson where we had 2 excellent examples.
OK, live and learn. Next time I'll be a little truer to ingredients and technique. And of course I'll have to 'research' at our local tacquerieas first....