sour dough starter: mix 1 C unbleached flour with 1 C warm water. every 24 hours throw away half of mixture and feed it with 1/2 C unbleached flour and 1/2 C warm water. after about four days it should have a pleasant sour or slightly beery smell. if not, carry on a couple more days. if so, put it in the frig. to use, take out and bring to room temp. add 1/2 C unbleached flour and 1/2 C water and mix well. it is ready to use in any of your sourdough recipes. be sure you leave some behind to keep feeding for next time.
yogurt: 3 C whole milk, 1 C half and half, 1 t. unflavored gelatin, 1/2 powdered milk, 3-4 T yogurt. you can adjust the fat content (not everyone wants high fat yogurt like i do) by using any kind of milk you don't feel guilty about, although i hear that full fat yogurt is in style this year. blend the powdered milk into the other milk. soften gelatin in 1/4 C cold water. take everything (EXCEPT THE YOGURT) and put it in a pan. heat just until it starts steaming. let cool off to lukewarm, then gently mix in yogurt. this yogurt will yog (YES, yog) nicely in a yogurt machine, or you can put it in a canning jar in a gas oven, the pilot light will keep it warm enough. i even tried it with a heating pad once (forget it, it didn't work). yogging it for 12 hours will make a very sharp flavored yogurt. 6 hours for a mild yogurt, and anywhere in between for whatever you want. i left it in for 17 hours once and it took the enamel off my teeth.
sweet potato slips. take a sweet potato from the grocery store, suspend it in a jar of water with toothpicks (yes, just like you did when you were a kid). when you get a 3-4 inch "slip," cut it off with a little piece of the sweet potato attached and set it in potting soil. collect as many as you want/can. then when not only the danger of frost is past but the soil has warmed up (may in north carolina) plant your slips. they like to grow on a ridge covered with black plastic in cooler regions, to keep their roots nice a warm.