Organic yogurt is expensive. It can be really expensive. I don't know about you, but I can't afford $3.50 or $4 per quart of yogurt at the store--and that's just the store-brand organic yogurt. A while back I started making my own yogurt with soy milk in the slow cooker based on inspiration from the Crock Pot 365 blog. I now make it with local dairy, but with the same technique. This is a really basic recipe, but you really can't go wrong with it if you pay attention to the temperature. Crock pots insulate foods very well, so culturing the yogurt has always worked perfectly for me. And no expensive yogurt maker necessary. Make this plain like I do, and mix in fruit preserves if you like when you're ready to serve. I like mine simple--with fresh or dried fruit and a drizzle of local honey.
Easy Slow-Cooker Yogurt
1/2 to 1 gallon organic whole milk (preferably local and raw if you can get it)
1/2 cup organic whole milk plain yogurt
Pour the milk into your slow-cooker. Cook on low for 2 1/2 to 3 hours, or until the milk has reached 170 degrees F. Do not allow to boil. Turn off and unplug the slowcooker; let sit for three hours or until the milk temperature has reached 110-115 degrees F. (If the milk is warmer than that it will kill the live cultures and you'll just get sour milk.) Remove about 1 cup of milk and whisk with the 1/2 cup yogurt in a bowl. Return the mixture to the crock pot and whisk until well-combined. Cover the crock pot again. Wrap with 1-2 large bath towels for insulation; let sit overnight (12-24 hours). Divide into airtight containers and refrigerate until chilled, or for up to three weeks. Remember to save 1/2 cup of your yogurt for the next batch.
*For Greek-style yogurt: After the yogurt has cultured, line a colander with a clean dish towel and place over a large bowl. Add yogurt in desired amount. Place the bowl and colander in the refrigerate and allow to drain for several hours, or overnight. Allow 3 cups of the above yogurt per 1 cup desired Greek-style yogurt yield. (Use strained yogurt instead of sour cream in recipes, if you like... It's super versatile!)
Cost per recipe (1 gallon organic milk yogurt): about $5.50-$7, depending on the dairy.