- 2 tablespoons olive oil
- 2 cups chopped onions or thinly sliced leeks (whites only)
- 1 cup thinly sliced celery
- 2 teaspoons Italian seasoning
- Coarse salt and ground pepper
- 3 cans (14 1/2 ounces each) reduced sodium vegetable broth
- 1 can (28 ounces) diced tomatoes, with juice
- 1 tablespoon tomato paste
- 8 cups mixed fresh or frozen vegetables, such as carrots, corn, green beans, lima beans, peas, potatoes, or zucchini (cut to larger vegetables into smaller pieces).
- 8 to 10 white mushrooms, washed and sliced
- Heat oil in a large stock pot over medium heat.
- Add onions or leeks, celery, and Italian seasoning; season with salt and pepper. Cook, stirring frequently, until onions are translucent, 5 to 8 minutes.
- Add broth, tomatoes and their juice, tomato paste, and 3 cups water to pot; bring mixture to a boil. Reduce heat to a simmer, and cook, uncovered, 20 minutes.
- Add vegetables to pot, and return to a simmer. Cook, uncovered, until vegetables are tender, 20 to 25 minutes. Season with salt and pepper, as desired.
Let cool before storing.