Lentil Soup

This one-hour soup is surprisingly easy to prepare, considering how pleasant it tastes. Lentils are a nutritious source of fiber. It makes a hearty winter soup combined with a small amount of sausage and plenty of vegetables.
Remove the casing from the sausage. Preheat a 4-quart saucepan over medium-high heat. Pour the oil into the pan; stir to coat. Add the sausage to the pan and cook until it is lightly browned; stir until it crumbles. Add the onion, celery, and carrot; simmer for 4 minutes or until tender. Add garlic; simmer for 30 seconds.Add 7 cups of water and the following 6 ingredients (via bay leaf). Bring to a boil; add the lentils. Bring back to the boil; reduce the heat and simmer uncovered for 40 minutes or until the lentils are tender.Add the spinach; cover and cook for 2 minutes or just until the spinach wilts. Remove and discard the thyme sprigs and bay leaf. Pour the soup on plates and, if desired, sprinkle evenly with cheese.