Heat the olive oil in a large pot over medium heat. Add the onion, carrots, celery, and garlic and cook, stirring occasionally, until the vegetables are soft, about 8 minutes. Add the oregano, cumin, paprika, thyme, cinnamon, nutmeg, and black pepper and cook, stirring, for 1 minute.
Add the vegetable broth, tomatoes, lentils, and bay leaf and bring to a boil. Lower the heat to a simmer and cook, stirring occasionally, until the lentils are tender, about 45 minutes.
Stir in the half-and-half and salt and cook for 5 minutes more. Remove from the heat and discard the bay leaf.
Serve the soup garnished with the parsley.
Interesting Facts
This soup is named after the city of Rhinelander, Wisconsin.
Lentils are a good source of plant-based protein and fiber.