Place the potatoes in a large pot and cover with water. Bring to a boil and boil potatoes until they are fork-tender, 15-20 minutes. Drain the potatoes.

While the potatoes are boiling, sterilize a glass container, such as a bowl or Pyrex container. I do this by placing the container in a clean sink and pouring boiling water over it. Remove the container to the counter and place on a clean towel to cool.

In the pot or a large mixing bowl, add the kefir and salt to the potatoes. You can use a potato masher to mash the mixture, or blend it all in a food processor for a very smooth texture.

When very well blended, place the mixture in your sterilized glass bowl or container. Cover and place on the counter to ferment. Leave on the counter for 2-3 days.

After 2-3 days, the mixture will have a mild tangy aroma. Transfer the mixture to a clean linen or cotton towel. Tie the end of the towel and hang it up from a cupboard handle. Place a mixing bowl underneath and let it drain.

When the dripping has stopped (I sometimes squeeze it once to get the excess from the towel) remove the towel from the handle.

Add any herbs or seasonings of your choosing. Serve your potato cheese as a dip or a spread. Store tightly covered in the refrigerator.