Heat olive oil in a large pot over medium heat. Add onion and cook until soft (about 5 minutes). Add garlic and cook for 30 seconds.
Add chopped tomatoes and cook for about 5 minutes until slightly softened.
Pour in the broth and bring the mixture to a gentle boil.
Add carrots and potatoes. Simmer for about 10 minutes.
Stir in zucchini, green beans, corn, and optional vegetables. Continue simmering until all vegetables are tender (10–15 minutes).
Add cumin, oregano, salt, pepper, and chili powder if using. Adjust to taste.
Stir in fresh lime juice and cilantro just before serving. Serve hot.