Place ground coffee into a gallon (4L) container. Fill with cold water, wetting all the grounds. Place a lid on the container and let it sit on the counter or in the refrigerator for pre-chilled coffee, for 12-24 hours.
Stir the coffee and then let it sit a few minutes to let the grinds settle at the bottom of the container. Scoop or pour the coffee off the top of the container through a filter or cheesecloth. This yields almost three quarts/ litres of cold brew coffee.
Chill completely in the refrigerator. Homemade ice coffee will keep in the refrigerator for several weeks.
Fill a mug or glass halfway with coffee concentrate.
Fill with almost another half glass of milk.
Add 1-2 tbsp sweetened condensed milk. Stir well.
Add ice. Relax and enjoy!