During coronavirus lockdown, we’ve practiced brewing better coffee at home in lieu of visiting our favourite coffee shops. Now, as summer approaches, it’s the perfect time to learn how to make Japanese iced coffee in our own kitchens.

Acolytes of the Japanese method say it tastes better than cold brew, and while cold brew needs to sit overnight, Japanese iced coffee can be made in under 10 minutes.

“I think it is a superior method to cold brew, since you get a chance to unlock more flavour from coffee compounds with the hot water extraction, while still getting an equivalent body as if it were a cold brew,” said Julie Nguyen, co-owner of Contra Coffee and Tea in Orange, California.

How it’s different from cold brew

The name derives from a method that’s been used in Japan since the 1920s, but it also refers to the use of Japanese coffee equipment, like Hario products, to brew it. Some coffee shops refer to this method of making coffee as flash-brewed, flash-chilled or just iced coffee.

To make it, you pour just-made coffee over ice cubes, shocking the brewing process to prevent bitterness from developing. Dumping ice into already-made hot coffee creates acrid flavours, but slowly dripping brewing coffee over ice can extract complex flavours from the coffee and flash chills it.

Nguyen, who has a background in food science, explains more: “The coffee must drip directly onto the ice immediately after the extraction begins,” she said. “We believe this is the key characteristic of Japanese iced coffee, because this critical step stops the development of acids in the brew.”

Brett Barker, co-owner of coffee roaster Wood Burl in Dayton, Ohio, and local coffee shops Press Coffee Bar, has been offering Japanese iced coffee for six years. “When customers ask the difference between cold brew and iced coffee, I say Japanese coffee has that really crisp, clean flavour,” he said. “It’s not weaker than cold brew, but it has a lighter body and it’s got those crisp flavours like an iced black tea.”

So how does the Japanese method compare to standard cold brew? Cold brew can take up to 24 hours to steep, whereas the Japanese process takes less than 10 minutes. The only downside to Japanese iced coffee is that it produces much smaller batches than cold brew. 

Here’s how to make it at home

To make it at home like a barista, you will need:

• a scale (Barker recommends the Jennings CJ-4000.)

• coffee maker (preferably a Chemex or a Hario V60 dripper)

• grinder (He recommends the Baratza grinder.)

• whole coffee beans (He likes to use beans from Africa.)

• hot water (not quite boiling), preferably purified or filtered by reverse osmosis

• regular-sized ice cubes

To brew the coffee in a Chemex: Rinse a paper filter, dump out the hot water, weigh the ice, then weigh the coffee. Place the ice inside the Chemex. Brew your coffee by pouring hot water (not quite boiling) from a kettle onto the grounds and allowing them to drip over the ice cubes that are inside the Chemex. Typically, a 50-50 ratio of hot water and ice cubes works, but Barker said he likes to use a little more ice: “I say adjust to your taste. … If you like remaining ice, dial back your hot water.”

To brew the coffee in an automatic coffee machine: You’ll need to add more coffee grounds than you would when making a normal cup of coffee. For instance, if you normally add four tablespoons of grounds, double that. “We’re making this way overdosed ground coffee and then a very under-extracted concentrate hot brew,” Barker said.

Experiment to get your perfect cup

“It’s all about attention to detail,” Nguyen told HuffPost. “It’s important to know that each bean you use and how it’s ground will most likely have a different water-to-ice ratio that you will have to figure out.” Her recipe includes 30 grams of medium-fine ground coffee, 300 grams of hot water (at 200 degrees Fahrenheit) and 120 grams of ice. She prefers medium roasts but encourages experimenting with espresso and lighter roasts, too. “Try everything! You’d be surprised what you’d enjoy,” she said.

With a long summer ahead, you’re going to need something refreshing to cool you off. Check out Just One Cookbook’s helpful YouTube tutorial for Japanese iced coffee below: