The details of the current recipe: bring the water to a boil, then let it cool for 5-6 minutes. Put 10 tsp of hoji into a ball (in practice, this mostly fills our large tea ball), and put the ball into the carafe. Slowly pour the water in to fill, and steep for 2 minutes, agitating gently (basically just raising and lowering the ball slowly, to get some circulation). Take out the ball, cool to room temp, and chill.
The result is a lovely iced tea: dark as a "green" tea can imaginably get, strongly-flavored without major off-notes. It took a while to get past the idea of using that much tea, but it's still pretty cheap: 3.5 oz of basic Hoji (enough for about 5 32-ounce carafes) costs about three bucks at China Merch, compared with $1.50 per 12-oz plastic bottle of the commercial stuff. I'm not *quite* as good as the Ito-en variety yet, but I'm getting close enough to be more than worth the almost-tenfold price difference (and reduced garbage).
Now I just need the right travel cup to drink iced tea out of when I want to grab some for the road...