Are you a home yogurt-maker who wants thicker yogurt? The kind you can practically carve? Here's a simple trick that earned me the honorary title of "yogurt savior" from a friend.
Instructions for making yogurt can be found in cookbooks or online. But basically, yogurt has just two ingredients: milk and a live active culture. The culture can be bought in dry form, or you can use a few ounces of fresh yogurt instead.
You heat about one quart of milk to somewhere shy of boiling, then let it cool while stirring occasionally. Deploy a candy thermometer: When it drops to 116 to 118 degrees Fahrenheit, mix in the culture.
All that remains is to keep the mixture warm enough for a few hours that the friendly bacteria in the culture can turn your milk into yogurt.
One way is to submerge the container in warm water inside an insulated container; I use a plug-in "yogurt-maker," which is a lidded warming tray, like an incubator for microorganisms.
But yogurt made this way can turn out runny as porridge. The problem, I discovered through trial and error, lay in how quickly I heated the milk. Turn the stove burner too high, and the yogurt turns out runny. Keep it medium-low and the yogurt's thick. I find that a flame that takes 20 minutes to heat a quart of milk gives you yogurt that can stand on its own.