Place the onion, garlic, celery, and carrot in a large saucepan and stir in the tomatoes, red wine, vegetable stock and oregano.
Bring to a boil, cover, and simmer for about 15 minutes. Stir the beans and zucchini into the mixture and continue to cook, uncovered, for another 5 minutes.
Add the tomato paste and season well with salt and pepper. Heat through, stirring occasionally, and cook another 2-3 minutes but do not allow mixture to boil again.
Ladle the soup into warm bowls and serve with a spoonful of low-fat pesto on each portion. Serve with fresh crusty bread.
Place all of the ingredients in a blender or food processor and process for a few seconds until smooth. You can finely chop the basil and mix all ingredients together if no blender or processor is available.