1. 2 tablespoons olive oil
2. 2 cups chopped onions or thinly sliced leeks (whites only)
3. 1 cup thinly sliced celery
4. 2 teaspoons Italian seasoning
5. Coarse salt and ground pepper
6. 3 (14.5 ounce) cans reduced-sodium vegetable or chicken broth
7. 1 (28 ounce) can diced tomatoes, with juice
8. 1 tablespoon tomato paste
9. 8 cups mixed fresh or frozen vegetables, such as carrots, corn, green beans, lima beans, peas, potatoes, and zucchini (cut larger vegetables into smaller pieces)
- Heat oil in a large stockpot 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.
- Pour remaining soup in small batches into bowl of a food processor; carefully puree until smooth, and return to saucepan.
- Stir in cream; season with salt and pepper.
- Garnish with the reserved mushrooms, and serve hot.