Add coffee grounds and water to your pitcher, mason jar, or other container. Give it a stir to ensure that the grounds are evenly saturated with water.
Cover the container, place in the fridge, and allow to cold brew for 18-24 hours.
Place your mesh sieve over a bowl, pitcher or other vessel large enough to hold 4 cups of liquid. Line the sieve with your second layer of filtration.
Pour cold brew through sieve to filter.
You'll be left with a cold brew concentrate that can be diluted to your preference with water, milk or creamer. I typically enjoy a 1:1 ratio of concentrate to water, but experiment to find your perfect cup.
Transfer the cold brew concentrate to a pitcher, jar or jug that has a lid. It keeps well in the fridge for up to 2 weeks, but it will taste best if you drink it within the first week.