Sauté the base: In a large soup pot, heat olive oil over medium heat. Add onion, carrot, celery, and a pinch of salt. Cook until softened, about 8–10 minutes. Stir in garlic and parsley; cook 1 more minute.
Add veggies and seasonings: Add zucchini, green beans, and potatoes. Stir in the oregano, thyme, , salt, and pepper. Cook for 2–3 minutes to coat the vegetables in the aromatics.
Simmer the soup: Pour in the broth, water, and marinara sauce. Bring to a boil, then reduce heat and simmer uncovered for 20 minutes, or until vegetables are tender.
Add beans, spinach and pasta (or rice): Stir in the beans and pasta. Simmer until pasta is al dente, about 8–10 minutes. If using spinach or kale, stir it in during the last 5 minutes of cooking.
Adjust and serve: Taste and adjust seasoning. If the soup gets too thick, add a bit more broth or water. Serve hot with a drizzle of good olive oil, grated cheese, or a spoonful of pesto.