Take 1 quart jar and fill it with milk (I use a 2 qrt jar from Michaels), add 2 heaping spoons of yogurt as a starter (raw is better), stir well.  The organisms in the starter will work with those in the milk.  Fermentation will proceed most easily at temperatures over 80 degrees but to preserve all the enzymes in the milk, do not heat over 100 degrees.  Cover (I put a plastic sandwich bag between jar lid and jar top) and place in a cooler with a  heating pad.  I set my heating pad at medium keeping the temp between 85 and 100 degrees to get a tasty product that is more sweet than bitter. When the milk "sets up" or "jells" and looks like yogurt with a cream top (typically with in 18-36 hrs), fermentation has turned it into clabbored milk or yogurt, and it is ready to eat or refrigerate.  If it sets for too long it will become bitter.  YOu will have to experiment with the temp and timing till you get the taste you prefer.

Raw Yogurt Recipe: By Dr. Ron Schmid, "The Untold Story of Milk"

1 large onion
6 large tomatoes
2 green peppers
3 big cloves of garlic
jalapenos to taste (seeded)
lots of cilantro
juice of lemons or limes to taste
2 tbl. whey or kimchee juice
1 Tablespoon of Celtic Sea Salt

*Go easy on the peppers because fermentation causes them to be hotter then usual . . . .
*Please don't use powdered whey.  Make your own from raw milk or order from the farm.

Mix ingredients well in large bowl, stir and put into mason jars. Set the jars out on the kitchen counter from 1-4 days to ferment but don't seal.  Store them on plates in case juices flow out during fermentation.  These jars can explode if enough pressure builds so just let the lids sit without clamping.  After sitting out, wipe them off, seal them and refrigerate to slow the fermentation process, letting the jars burp the first couple days. This salsa will last for months.  Whey is a natural presevative. 
Lacto-Fermented Salsa:

Steam and drain yellow squash & onions (make about 4-5 cups)
1 cup bread crumbs
1 cup white cheddar cheese
1 cup heavy cream or milk (you can use soured         cream or milk)
3 eggs
cayenne pepper to taste
thyme to taste

Mix all ingredients and pour into a 9 x 9 dish.  Cover with 1/2 cup chedder cheese and 1/2 cup bread crumbs.
Bake 30 min. 350 degrees covered . . .10 uncovered.

Yellow Squash Recipe: