Hearty Potato and Sausage Soup

Saute the celery in bacon fat or olive oil for 5 minutes (I use bacon fat for flavor), then add the onions. Cook until nearly done, since the potatoes won't take long to cook. Add the cumin and hot pepper a minute or two before you add anything else - cumin benefits from a brief saute in oil. Then add in the potatoes and stir it all together to combine. Add water within about an inch short of covering the potatoes. Add the bouillon and the marjoram. 10 minutes before potatoes are done, add the sausage and simmer briskly. When the potatoes are tender, remove the sausage and keep warm. Mash some of the potatoes right in the pot, if you want the soup a bit thicker. Then mix the yogurt and milk and stir it in slowly, stirring the whole while. Bring the soup back to a simmer, and remove from heat. Serve.