"Sake on ice? Are you serious?"... is usually the response I get when I tell people it's one of my favorite ways to enjoy sake in the summer.
But you can't just pour any sake on the rocks. The best sakes to pour over ice are genshu sakes. Genshu sakes have not been diluted with water prior to bottling (or canning), so they are typically higher in alcohol (ABV 18-19%) than regular sake (ABV 15%).
It's been hot in Oakland and there's nothing more satisfying than popping open a can of genshu, like a Kikusui Funaguchi Gold, and pouring it over a big block of ice. It's fruity, smooth and refreshing. Having a genshu on the rocks opens up the flavor of the sake and dilutes it at the same time so it's a little bit more mild.
I've also really been into having the Kikusui Funagushi Green Shinsei one cup on ice with a lemon garnish. The lemon peel brings out the bright, fresh grassiness of the sake that's brewed with shinmai (first harvest rice).
Drinking sake on the rocks is so simple, just put a big block of ice in a rocks glass and pour your sake over it (preferably a genshu sake). If you want to be fancy, try the Kikusui Funaguchi Green Shinsei on-the-rocks with a lemon garnish.
Think I'm crazy for pouring all this sake on ice? Well, there seems to be a sizable amount of sake-on-the-rocks devotees in Japan. So much so, that there is a Nihonshu Rock festival every year in Osaka. I wish could have gone this year – it just happened last week!