If you have the time and foresight, soak your lentils in 6 cups of water for 12-24 hours. This will improve their digestibility, by removing some of the lectins present in legumes. Drain and rinse before use.

In a large heavy bottomed pot, cook bacon over medium-low heat until bacon is done to your liking. Remove from pan using a slotted spoon, and set aside. Drain all but 4 tablespoons bacon fat from the pan (save and use for another time).

Over medium heat with the remaining 4 tablespoons of bacon fat in the pan, add onions, celery and carrots along with a big pinch of salt. Cook for about 8 minutes, stirring often, until onions are translucent and take on a bit of color. Then add garlic, and cook for 1 minute more, stirring to prevent the garlic from burning.

Immediately add tomatoes and their juices, and stir well to bring up all the flavorful bits stuck to the bottom of the pan. Then add potatoes, 5 cups chicken broth, chopped herbs, and bay leaves, with a few pinches of salt and freshly ground black pepper.

Cook over medium heat for about 30-35 minutes, uncovered, until the potatoes and lentils are tender. If the soup is thicker than you'd like (lentils and potatoes absorb a lot of liquid), add 1-2 cups more chicken broth or water towards the end, then simmer for a few more minutes.

Taste for seasoning, and add more salt and pepper as needed, remembering that you will be serving the soup with bacon which adds its own saltiness.

To serve, top each bowl with bacon, fresh parsley, and sour cream if desired.