Making your own yogurt is like growing your own vegetables, but it happens overnight. The yogurt you get out of it is delicate, cheap, and way better than that gelatinous stuff you get in the store.
Step one: Heat your milk to 80 C. Heat it in a double boiler like this, so it doesn’t burn:
Step two: Cool the milk. Do this by putting your yogurt vessel into a sink full of cold water. Do this so the milk is the right temperature (40 C) for the yogurt bacteria.
Step three: Add your starter yogurt. You can just dump it in, or whisk it in. I don’t think it really matters.
Step four: leave on a heating pad overnight. Keep the innoculated milk at around 35 C for 7-12 hours.
In the morning, stir the thickened yogurt into the greenish whey that will be floating on top. Put your finished, but warm, yogurt into the fridge and let it cool. It will be ready to eat after a few hours. After a few days it will be noticeably thicker.
There, you’ve done it. All-natural, tasty yogurt. You’ve made cows everywhere proud.