This is a great way to make yogurt without all the chemicals found in most store brands(especially GMO corn starch) but it does take too long. I did a little experiment yesterday(2nd time making yogurt). I took two small glass jars with equal amounts of ingredients as the recipe calls for in each one, one covered and one open, put both in an uncovered pot with water higher than the ingredients in the jars, put on the electric burner the lowest setting possible to keep it around 110 degrees for 12 hours(still have to turn it on and off manually so it's not too hot). The yogurt without the lid ended up much thicker than the one with the lid but both are usable. I also used vanilla yogurt as my starter and seems to work fine. Why do recipes always say to use plain yogurt as a starter?