In a large pot, heat the olive oil over medium heat. Add the diced onion and sauté for about 3-4 minutes until translucent.
Stir in the minced garlic, diced carrot, and diced celery. Cook for an additional 5 minutes, stirring occasionally.
Add the diced tomatoes (with their juice), white beans, vegetable broth, dried basil, and dried oregano. Stir well to combine.
Bring the mixture to a boil, then reduce the heat and let it simmer for 20-25 minutes, allowing the flavors to meld.
If using, stir in the fresh spinach and cook for another 2-3 minutes until wilted.
Season with salt and pepper to taste. Serve hot, garnished with fresh parsley.