Recent suggestion by a doctor that probiotics would be a beneficial addition to my eating habits and homemade yogurt was a good source got me making my own yogurt again. He claims any commercial yogurt lacks the necessary amount of healthy bacteria. Another doctor named a brand of yogurt with extra pro'b's added but when I checked the ingredients on this – whooof. I get nervous when I don't recognize or can't pronounce such things.
So here is how I learned to make yogurt in India many years ago with slight adaptations.
Put one pint of milk in pot (I use a heavy bottomed one: makes cleanup a snap) on stove over medium heat and let it just come to the almost boil stage – bubbles will form around the edges and the top of the milk looks thickish.
Remove from heat immediately and let stand (I set timer for 15 minutes and then make first test) until you can dip a finger into the milk and have it still quite warm but not hot enough to make you pull hand out.
I find this method of testing very satisfying in its simplicity and reliance on my direct gauging.
Put two tablespoons of the last batch of yogurt into an insulated travel mug that will hold a pint of liquid.
If this is the first time making homemade use the plainest commercial yogurt you can find for the starter.
Pour the cooled milk on top of yogurt starter.
Put lid on mug.
Put mug in a spot where it will not be disturbed for the next twelve hours.
In India we used a bowl instead of a mug, wrapped it in a cloth and set it away in a cupboard for overnight.
I put cold water in the pot and let it sit for a few minutes; then it cleans up nicely with a scrub cloth. I have had milk stick to pans and practically need a chisel to get it out. Search around for a pan that doesn't do this: the frustration is not worth it.
This is what it looks like after twelve hours – yogurt!
Put in a container that closes and refrigerate.
Ready to eat. Tasty 'medicine'.