Sauté Veggies: Heat olive oil in a large pot over medium heat. Add onion and cook for 3–4 minutes until translucent.
Build Flavor: Add carrots, celery, and bell pepper. Sauté for 5–6 minutes, stirring occasionally.
Add Seasoning: Stir in garlic, Italian seasoning, pepper, and salt. Cook for 1 minute until fragrant.
Pour Broth: Add vegetable broth and bring to a boil.
Add Main Veggies: Stir in cabbage and tomato. Reduce to a simmer.
Simmer: Cook uncovered for 15–20 minutes or until vegetables are tender.
Finish: Stir in white-wine vinegar and any optional ingredients. Adjust salt and pepper to taste.