Scoop 1/4 cup of the plain whole milk yogurt into a clean, wide mouth, glass mason jar (I like these). After you've made raw yogurt one time, you can use your own raw yogurt as the starter for subsequent batches.

Warm the raw milk on the stove to between 105 - 117F. No enzymes or nutrition is lost heating to this temperature but the warmed milk enables the yogurt culture to "take" better than room temperature raw milk.

Pour about half a cup of the warmed milk into the mason jar and mix with the yogurt.

Pour the remaining warmed milk into the mason jar, stir and close the lid tightly.

Wrap the mason jar in a thick hand towel, secure with a rubber band and place inside your microwave closing the door. Leave the light in the microwave on to keep a bit of warmth inside.

In 24 hours, open the microwave and voila! You will have yourself a lovely quart of raw yogurt!