Over low heat, slowly heat milk or cream to 86 degrees F, then remove the milk from the heat. The milk should be heated no faster than a rate of 1 degree per minute. This can take 30-40 minutes for a gallon of milk.
Add 1 packet of cream cheese starter and mix thoroughly, using an up-and-down motion rather than a stirring motion. Do not mix for longer than 15 seconds.
Cover the pot with a lid and culture in a warm spot for 12 hours at 72-77 degrees F.
After 12 hours the cream cheese should be set. Place a colander in a bowl and line the colander with a tight-weave dishtowel or double layer of butter muslin.
Spoon in the curds, and then gather up the corners of the cloth and tie the ends together to make a bag.
Hang the cloth filled with cream cheese over a bowl to drain the whey for 6-12 hours at 72-77 degrees F.
Knead salt into the cheese to flavor it.
Store the cream cheese in a closed container in the refrigerator for up to a week. To freeze it, remove as much whey as possible and salt your cheese well using cheese salt before freezing.