Trust me on this one, the only tricky thing about making yogurt is keeping the temperature at the right place. The rest is no harder than mixing up a cake mix!
So here's what you'll need:
3 1/2 C. Skim milk in a glass Pyrex measuring bowl
1/2 C powdered milk (this is added to make thick yogurt)
2 Heaping TB of plain, "live" or "active" yogurt culture Just check your plain yogurt container to make sure it has one of those words on it (most of them do)
Heat the powdered milk to your skim milk, and heat to almost boiling in the microwave. Let it cool down to around 115-118 degrees. Add your yogurt to a quart mason jar, and add half of your milk. Put on the lid and shake it up really well.
Then add the rest of the milk, and put your mason jar in a small cooler with a heating pad. (This is the way that I do it, there are various other ways to provide consistent heat. Keep the temperature between 110-120 degrees for 6-8 hours. Mine is usually done in 5 hours. When you refrigerate it, it will firm up a little more, so don't worry if it's not a perfect consistency.
This is the cooler, heating pad, and thermometer that I use. This was a doubled batch.
(I was out of the jar lids, so I used tin foil instead if you're wondering ;-)
Taa daa! You have your own home-made yogurt! You can use a culture from this batch, and the next batch and the next until your culture "goes bad" or loses the good bacteria it uses to create yogurt. You can freeze yogurt so that you will never run out of extra to make a new batch.
Try mixing it with bananas, blueberries, strawberries or raspberries. They help sweeten it up if you're trying to get away from using sugar. It makes a great breakfast! I like to slightly defrost frozen blueberries and strawberries, smash them up and mix with a couple tablespoons of yogurt. Yummmmm!