Excellent cold brew is easy to make, though it takes a bit of patience to let it steep for at least 48 hours. For the coffee, you need a glass bottle with the cap. European refrigerators are small, so I use one-liter bottles, and I make 4 liters at a time.
You only need two ingredients.
- Your favorite roasted coffee, coarsely ground
- Water that tastes good
Use the best-tasting water you can find. In Switzerland, the water out of the tap is fabulous, but if you live in a region with swampy or highly chlorinated water, buy spring water. Try a taste test for different brands of bottled water — not all spring water tastes the same. Use only water you’d be glad to drink on its own.
The recipe is simple: add 5 parts water to 1 part ground coffee. Add the coffee to the bottle, then add the water, swirling to wet all the coffee grounds. The coffee will foam a bit, so let the foam settle and then top the bottle off with a bit more water. Put the filled bottles in your refrigerator.
The coffee will all rise to the top, so an hour later shake each of the bottles. Now the coffee will settle to the bottom. Let the bottles sit in the refrigerator for at least 48 hours.
Strain as you pour. Add milk or cream to taste. You may need less sugar than usual in your cold brew because there is no bitterness. The coffee is great cold or you can warm it in the microwave. If you heat it, make sure not to boil it because it will get bitter if you do.
Because cold brew isn’t bitter, you can taste differences in between types of coffee much more easily. I have settled on a Honduran or a Peruvian crema as my go-to flavor, but you can try this with whatever beans you like. Heavily roasted beans tend to have strong caramel and chocolate flavors, while with light roasted beans the tones are much more varied. Experiment and have fun!
I find my cold brew tastes better every day, for up to a week. Then it tends to get nasty, but it almost never lasts long enough to go bad, no matter how much I make.
When you’re done with the coffee, throw it on your compost heap because the ground are great for the plants!
Note: Coarsely ground coffee is a lot easier to filter out later and I think it’s easier for the water to penetrate. I buy beans and grind them fresh.