Blanche the salt pork to remove the salt, by soaking in cold water for two hours and changing the water several times. Drain the water one last time and than fill the pot with about 2 quarts of water, covering the salt pork. Place on low heat to simmer at a very low boil for one hour.
Push 4 or 5 cloves into the onion and add to the pot (this is called an oignon picquet and is a popular way to add subtle flavor to soups and stews in France). Add the lentils, baby onions or chopped onion, carrots, bouquet garni and several pinches of pepper. Cook on medium low heat for 40 minutes to an hour, adding more water if necessary. You want the final product to be just slightly soupy.
Meanwhile boil the sausage in a pot of water. The sausage I used required 25 minutes of boiling, but follow your package directions for cooking times.
Once the lentils are cooked, remove the salt pork and the bouquet garni. Cut the salt pork into bite sized pieces and return it to the pot. Cut the sausage into small pieces as well and add it to the soup.
6 servings.