If you’re one of the many iced coffee lovers who’ve made the switch to cold brew, you may be wondering what all the fuss is about “flash brewed” iced coffee. Back before cold brew was a thing, iced coffee was often regular strength hot coffee (or yesterday’s coffee) poured over ice. The result was watery and disappointing. Also called ice brewed or Japanese-style iced coffee, flash brewed iced coffee is brewed fresh over ice, usually using a pour-over brewer like the Chemex or Hario. For a visual, check out our video on brewing hot or iced coffee with the Chemex. It can also be made with a regular old automatic drip machine or an Aeropress. The key is allowing the coffee to drip directly onto the ice as it brews. Drip by drip, it cools instantly and less dilution occurs than if you were to dump a cup or a pot full of hot coffee over ice.

Flash brew vs. cold brew

If cold brew tastes a little flat to you, that’s because ground coffee requires heat to release some of its acids and aromatic oils (for details on the cold brewing method, check out our post). Cold brewed coffee is much less acidic, but possibly also less nuanced in flavor. High temperatures also cause these oils to oxidize and degrade over time, resulting in the sour or stale taste coffee acquires after sitting on a burner too long. Both methods claim to minimize oxidation, cold brewing by omitting heat and flash brewing by minimizing the amount of time between exposure to heat and consumption.

Another important difference between cold brew and flash brew is texture. Cold brew is less filtered since the coffee sits in contact with the grounds for a long period and some finer sediment dissolves over time. The end result is a rich, mellow cup, with the velvety texture of French press coffee. Flash brewed coffee by comparison is cleaner and crisper, with more bite, more aroma, and some would argue, more flavor.

Flash brewed coffee also has a few convenient advantages over cold brews, depending on your perspective. While nothing is lazier than dumping grounds and water in a bowl and letting them sit, flash brewed coffee is ready right away – no wait required. Also, less coffee is required since cold brew recipes typically make a concentrate with a high ratio of grounds to water. For flash brewing, start with the amount of coffee you would normally use, and replace half the brewing water with ice. Increase the grounds to water ratio if you like a little stronger taste from your iced coffee.

So which one wins? Cold brewing will emphasize more chocolaty or nutty characteristics while the acidity of flash brew will taste fruitier. Try picking a single origin coffee with an acidity level and flavor notes that will either play up or balance these characteristics. For instance, the higher acidity level of Ethiopian Yirgacheffe really jazzes up a cup of cold brew. To further emphasize its brightness, try it flash brewed. To minimize the acidic flavor of flash brewed coffee, try an Indonesian varietal like Papua New Guinea or Estate Java. Flash Brewed coffee tends to have a more nuanced flavor, perfect for a light roast coffee, but there are no rules. Experiment with roast level, see what you like, and share your recommendations!

Why would a person make drip coffee by hand, when there are machines for that?

If you’ve noticed the line moving more slowly at your local fancy coffee shop, pour over coffee may be to blame. The basic process involves pouring water by hand in a slow stream through grounds in a filter to produce a single cup or small batch. If this sounds like what your drip machine does, but slowly and with lots of room for human error, you are correct.

So why is this popular? Pour over is known for having a fuller, more complex flavor than automatic drip coffee, and a brighter, less heavy flavor than French press. Not necessarily better, it can yield different or a range of results from the same coffee depending on the pour. Control over the temperature and flow of the water allows for more control over the flavor profile of the end result.

If you’re interested, but doubt your ability to manage more than a push of a button in the morning, you might be wondering if manual brewers are worth the effort. We picked the Hario V60 system to demonstrate how simple the process can be. If you use an automatic brewer, you already know the basic steps by heart: place coffee in a filter, place a filter in a cone, and add water. The big difference is that you pour the water by hand. You might want to experiment a little to get your pour down pat, but once you know the drill, you can easily make this a part of your routine.

Simple Pour Over Coffee: How to Hario from Coffee Bean Direct on Vimeo.

What you’ll need:

Hario V60 Dripper

Hario V60 Range Server

Hario V60 filters

Coffee

Tablespoon

Directions:

1. Boil some water in a kettle. The Hario we’re using holds 20 oz, but you can also brew a single serving with the same equipment. After boiling, set aside.

2. Fold a V60 paper filter along the seam for a better fit and place it in the dripper.

3. Optional: lightly wet the entire filter with a little hot water. With the dripper attached, pour the hot water out once it has drained through.

4. Place ground coffee into the filter. We recommend 2 tablespoons (1 coffee scoop) of medium-fine coffee per 6 oz of water. If you want to be fancy, level the grounds and make a divot in the center. This will encourage drainage though the grounds.

5. Pour just enough water into the filter to wet all the grounds and wait 45-60 seconds, about the time it takes to find a pop-tart and stick it in the toaster.

6. Slowly pour the remaining water over the grounds. The key to doing this right is to pour very slowly in circular motion and to keep the stream of water on the coffee. Try to avoid hitting the filter or the center directly. This is easier with a thin-spouted kettle, but any kettle or teapot can work if you go slow and keep the stream as fine as you can.

7. While the last of the water is draining, give the grounds a stir with a spoon.

8. Replace the dripper with the top of the server and swirl the carafe.

9. Pour, drink, and get on with your day.