1. Wash and chop the kale, removing tough stems.

2. Dice the onion, celery, and carrot. Mince the garlic.

3. Heat olive oil in a Dutch oven over medium heat.

4. Add onion, celery, and carrot and sauté for 5 minutes until softened.

5. Stir in garlic and dried thyme and cook for 30 seconds.

6. Add vegetable broth, white beans, bay leaf, salt, pepper, red pepper flakes, and chopped tomato if using.

7. Bring to a boil, then reduce heat and simmer for 15 minutes.

8. Stir in chopped kale and cook for 10 minutes until tender.

9. Remove the bay leaf and stir in lemon juice if using.

10. Ladle into bowls and garnish with Parmesan if desired.