Ingredients

• 3 cups chopped peeled celeriac (celery root)
• 2 cups chopped parsnips
• 1 cup chopped carrot
• 1 cup frozen pearl onions
• 1 stalk celery, chopped
• 2 medium plum tomatoes, seeded and chopped
• 3 cloves garlic, minced
• 2 teaspoons herbes de provence
• 8 cups low-sodium chicken broth or vegetable broth
• 1 cup french green lentils or black lentils, rinsed
• 1 sprig fresh rosemary
• 1 tablespoon (3 inch) rind parmesan cheese plus 1/2 cup shredded parmesan, divided
• 1 medium bay leaf
• 1 teaspoon salt
• ½ teaspoon ground pepper
• 4 ounces pancetta, crisp-cooked and crumbled (optional)