put it in 16 oz. mason jars in a large picnic cooler, with a heating pad on the bottom and covered by a heavy bath towel, to incubate overnight.

Now I heat the 1/2 gallon of (whole) milk in my CrockPot Express (comes out to around 175F), after it cools to 100F, I mix the starter, (tempering it with a little of the warm milk) and a cup of heavy whipping cream. Return to the Express for 8 hours to incubate. Refrigerate overnight and put in containers the next day.

It comes out nicely thick and creamy, full fat Greek style without any straining at all. Tastes good, not overly tart.

To keep items like yogurt and sour cream from separating, after serving the desired amount of product, smooth the top of the remainder in the container with the back of your spoon so there aren't any wells or low spots, just a smooth mostly level surface (doesn't have to be perfect.) It won't separate or become thin and watery as long as you continue to do that each time before putting it back in the fridge.