In a large saucepan or soup pot, heat the oil and add the chopped onions. Put the lid on and sweat the onions for about 5 minutes.
Add the chopped zucchini and continue to cook with the lid on for about 5-10 more minutes until soft and a little caramelized. Stir in the garlic until fragrant. **If you prefer the texture of the chopped zucchini, then add the garlic to the onions and add the zucchini with the carrots, skip the next step and add the liquid all at once.)
Pour in 2 cups of the chicken broth and bring to a boil and then puree everything with an immersion blender or by pouring into the blender being sure to let the steam escape.
Now add the carrots, white beans, rosemary, salt & pepper. Then pour in the remaining 2 cups of chicken broth and 2 cups of water & stir everything.
Bring everything to a boil over a medium flame. Once boiling, turn the heat down and simmer for 20-30 minutes until the carrots are to your desired tenderness.
Place a little of the spinach into each serving bowl, ladle the soup over & garnish with the parsley, grated parmigiano & fresh lemon juice.
Store any leftovers in the fridge and enjoy for up to 3-4 days.
If using dried white beans like I did you can cook them using your preferred method or this way:
-Either soak 1 cup white beans in a large bowl of water overnight, or for quick-soak method, pour boiling water over the beans and soak 1 hour.
-When finished, drain, rinse with cold water and add to a large pot. Cover with about 5 cups of water, bring to a boil, and then simmer over a low heat for about 1 1/2-2hrs until tender. (they will soften a little more in the soup.)
-proceed with the soup recipe using some of the cooking liquid from the beans in place of the water or broth.