Cold Brew Coffee

Method

1. 1Grind the coffee. If starting with whole beans, grind them to a medium-coarse consistency — the grounds should look roughly like kosher salt or coarse sugar, not fine powder. Too fine and you'll get a bitter, cloudy concentrate that's difficult to filter. Too coarse and the cold water won't extract enough flavor in the time available. Pre-ground coffee from a standard bag works in a pinch (the grind is a bit finer than ideal), but whole beans ground fresh give a noticeably cleaner result.
2. 2Combine coffee and water. Add the ground coffee to a large jar, pitcher, or French press. Pour the cold filtered water over the grounds and stir gently to make sure every particle is wet — dry pockets of coffee at the top will not contribute to the brew. Cover tightly with a lid or plastic wrap. Filtered water makes a real difference here: chlorine in tap water creates off-flavors that are more noticeable in cold brew than in hot coffee because there is no heat to drive them off.
3. 3Steep in the fridge. Place the covered container in the refrigerator and leave it for 14 to 18 hours. Sixteen hours is the sweet spot for most people — smooth and rich without any harshness. Do not exceed 20 hours: beyond that, the brew picks up a sharp, almost whisky-like bitterness that no amount of dilution fully corrects. If you forget and leave it overnight plus the next day, taste it before committing — it may still be fine.
4. 4Strain the concentrate. Place a paper coffee filter inside a fine-mesh sieve and set it over a clean pitcher or jar. Pour the coffee and grounds through slowly, letting gravity do the work. Do not press or squeeze the grounds — this forces bitter compounds through the filter. The draining takes about 5 to 10 minutes. Once strained, discard the grounds immediately. Every hour the concentrate sits with grounds continues the extraction and builds bitterness.
5. 5Dilute and serve. For a standard glass: fill a tall glass with ice, add 120 ml of cold brew concentrate, then top with 120 ml of cold water (a 1:1 ratio). For a latte-style drink, replace the water with whole milk or oat milk. For a stronger coffee, use a 2:1 concentrate-to-water ratio. Taste and adjust. Store the remaining concentrate in a sealed jar in the fridge for up to 14 days — the flavor is best in the first week.