Fresh basil adds a bright spark to this vinegary, vegetable-stuffed soup, full of the traditional flavors of the Mediterranean. Alternatively, pesto adds a nutty richness to the soup.
Heat oil in a Dutch oven over medium heat. Add onion, cover and cook, stirring occasionally, until beginning to brown, about 6 minutes. Add paprika and cook, stirring, for 30 seconds. Add broth, tomatoes, squash, potatoes and beans; bring to a boil. Reduce heat to a simmer and cook, stirring occasionally, until the vegetables are just tender, about 12 minutes. Stir in spinach and vinegar; continue cooking until heated through, 2 to 4 minutes more. Ladle soup into bowls and top with fresh basil or a dollop of pesto.
Ingredient Note: Convenient cooked and diced potatoes can be found in the refrigerated section of the produce and/or dairy department of the supermarket.