Yogurt

Have you ever tried to make yogurt? I have...several times. The first time, it worked (amazingly enough). However, after that, things went down hill. My troubles?

First of all, I have come to the conclusion that yogurt cannot be made with highly processed (UHT) milk. (I tried this twice before giving up) Secondly, yogurt cannot be baked at a temperature of 350F. How do I know this? (Besides common sense) I experienced this first hand yesterday.

Having spent eight hours trying to maintain a perfect 110F, I failed to mention to my housemates that I had yogurt in the oven. One of our girls came home yesterday afternoon and promptly pre-heated the oven to 350F in preparation for a batch of brownies. All my efforts had been for naught! Of course, not wanting to lose my eight hours of work, I tried to rescue my creation. However, the rubber-like substance simply could not be salvaged. Ah...well...