In a large Dutch oven, over medium heat, heat the oil, swirling to coat the bottom.
Cook the onion, celery and garlic for 4 to 5 minutes or until the onion and celery are soft.
Stir in the broth, beans, tomatoes with liquid, oregano, black pepper, Italian spices, Greek spice, red pepper flakes and thyme.
Increase the heat to medium-high and bring to a simmer, stirring occasionally; reduce the heat and simmer, covered, for 20 minutes so the flavors blend.
Stir in the spinach; simmer, covered for 2 to 3 minutes or until the spinach is wilted.
Optional – just before serving, sprinkle the soup with the Parmesan cheese.