To begin, I make sure I have clean jars ready for the finished product. I use quart canning jars because they are easy to handle from the fridge as opposed to one big gallon jug. Clean lids, a funnel, ladle and thermometer are essential items as well as a double boiler system.
*note-use stainless steel pan for the milk.
I set up a double boiler system with two very large pans, then the milk into top pan, turn the heat on high and stir to distribute heat and prevent any scalding, measuring temp often. You want to heat the milk to 161 degrees and maintain that for about 15 seconds.
Once the milk has reached 161 throughout, remove it from heat and immediately cool it down. I accomplish this by setting the entire pan into my kitchen sink and adding ice cubes and cold tap water to surround the pan. Then I stir, checking temp until the milk has cooled to at least 98 degrees or less. This takes about 10 minutes. (Some say cool to 40, but I allow the fridge to finish the job.)
Once cooled, I ladle into clean jars and place into refrigerator immediately to further the cooling process.