Grind coffee beans to a coarse grind. Add to a clean jar or pitcher that can hold at least 2 quarts.
Add cold water to the jar. Stir to thoroughly moisten the coffee grounds.
Cover jar and place in the refrigerator for 12 to 24 hours.
Line a fine-mesh strainer with cheesecloth and set it over a large measuring cup. Slowly pour the coffee through the strainer. Allow the coffee concentrate to slowly filter.
Transfer coffee concentrate to a clean jar or pitcher. Keep in the refrigerator for up to 2 weeks.
When ready to make a cup of cold brew, add equal parts cold brew concentrate and cold water over ice.
