Flash brew (Japanese iced)
also: Japanese iced coffee, flash-chilled coffee
Hot pour-over brewed directly onto ice, locking in aromatics for a bright, clean iced coffee.
Flash brew, often called Japanese iced coffee, is hot coffee brewed directly onto ice so it chills the instant it is made. You brew a normal pour-over, but replace part of the water with ice in the carafe, so the hot extract melts the ice and cools at once.
Why it matters: hot water extracts the bright, volatile aromatics that cold brew largely leaves behind, and flashing the coffee onto ice traps those aromas before they can evaporate. The result tastes lively, fruity, and clean, the opposite end of the spectrum from cold brew, which is smooth and muted.
How it shows up: a common starting point is to put about a third to 40 percent of your total water as ice in the carafe and brew the rest as hot water over the grounds. Because the ice dilutes as it melts, you use a slightly stronger ratio than for hot coffee to land in the right place. It is a percolation method, so grind size and pour control matter just as they do on a V60. Ready in minutes, not hours.