Add olive oil to a large pot over medium heat. Add onion, carrots, celery, and garlic and sauté for 5-8 minutes, or until softened. Add swiss chard stems, butternut squash cubes, dried herbs, salt, and pepper. Stir to coat in oil and spices and cook for 1 minute.
Add the remainder of the ingredients (except for swiss chard leaves and parmesan cheese) to pot.
Bring mixture to a boil, cover, reduce heat, and cook for 20-25 minutes, or until butternut squash is tender and lentils are cooked.
Stir in swiss chard leaves and cook until just wilted, about 1-2 minutes.
Divide into bowls and garnish with parmesan cheese, if desired. Enjoy!