Pour the ground coffee into the large mason jar. Then add the filtered water. Stir to saturate the coffee grounds.
Screw the lid on top of the mason jar, and place the jar in the fridge to brew for 10-12 hours.
When 10-12 hours have passed, remove the mason jar from the fridge.
Place the cheese cloth over a fine mesh sieve, then place both over a large container, preferably one with a spout for easy pouring after filtering the coffee.
Slowly pour the cold brew coffee through the cheese cloth and sieve. Discard the cheese cloth and leftover ground coffee.
Clean out the mason jar that was used for brewing the coffee, then pour the filtered cold brew back into the mason jar for storage.
Keep in the fridge for up to a week.
