This Horchata is the kind that is served in "neverias" or ice-cream shops in Mexico. It is creamy and easy to do. Grinding the rice twice brings out all the starch and flavor. Prep time is the time needed for the rice to soak. One reviewer stated that I don't know what I'm talking about and that the rice should be soaked overnight...if you choose to soak it longer, the result will be the same and you will still need to strain it as stated---twice. I do know what I'm talking about: I'm Mexican and live in Mexico.