Sauté the onions and garlic: Heat olive oil in a large pot over medium heat. Add the diced onions and garlic, cooking until softened and fragrant.
Add the carrots, potatoes, and celery: Stir in the sliced carrots, potatoes, and celery, and let them cook for a few minutes to enhance their flavor.
Pour in the broth and tomatoes: Add the vegetable broth, diced tomatoes, thyme, bay leaf, salt, and pepper. Stir everything together.
Add the cabbage and simmer: Stir in the chopped cabbage, bring the soup to a gentle boil, then reduce the heat and let it simmer for about 25 minutes until the vegetables are tender.
Add the beans: Stir in the drained white beans and let them warm through for 5 minutes.
Adjust seasoning and serve: Taste the soup and adjust the salt and pepper if needed. Remove the bay leaf before serving. Garnish with fresh parsley and enjoy warm!