adapted from Joy of Cooking
2 teaspoons olive oil
2 carrots, peeled and diced
2 celery stalks, diced
1 medium onion, diced
1 clove garlic, minced
1 pound Polish sausage, half of it diced, the other half sliced
8 cups chicken stock
1 bay leaf
2 cups lentils, picked over and rinsed
1 (14.5 oz can) diced tomatoes
1 sweet potato, peeled and diced
1 teaspoon dried thyme (I used basil, thyme would have been better)
salt and freshly ground black pepper to taste
Heat olive oil in a large soup pot over medium heat. Add carrots, celery, onion, garlic, and diced Polish sausage to the pot. (Reserve sliced sausage for later.) Cook, stirring occasionally, until vegetables are tender, about 10 minutes.
Stir in chicken stock, bay leaf, lentils, tomatoes, potato and thyme. Bring to a boil, reduce the heat, and simmer until the lentils and potato are tender, 30 to 45 minutes. Add the sliced sausage and cook for another 10 minutes. Season with freshly ground black pepper and salt if desired.