Japanese style iced coffee! As popular as cold-brew coffee has become, the prevailing opinion among coffee professionals, and the industry's worst-kept secret, is that it is utterly trash. What they know that you don't: Flash-chilled iced coffee is so, so much better.
Also known as Japanese iced coffee (pronounced aisu kōhī), flash-chilled coffee mimics the pour-over method for hot coffee, but does so directly over ice, whether via a Chemex, into a single-serving cup, or using a larger vessel for a bigger batch, as many coffee shops do. (In Japan's enviable 7-Elevens, you're handed a cup filled with ice to take to the machine that dispenses hot coffee.) Though Japan's specialty coffee shops had been serving much of its cold coffee flash-chilled already, the method didn't make it to the States until Peter Giuliano, then the director of coffee for Counter Culture and iced-coffee detractor, visited Japan in 1994. After being initially exposed to the method, Guiliano sought out specialty coffee master Hidetaka Hayashi for mentorship, and proselytized for the method upon his return. And despite Guiliano having his fair share of disciples today, flash-chilling has remained mostly an under-the-radar technique.
Read more here: https://www.thrillist.com/drink/nation/japanese-style-iced-coffee-cold-brew