To prepare a zucchini soup i recipe, you'll need: Zucchini: Wash and cut the zucchini in half lengthwise. Chop the flesh into small cubes. Add the cubed zucchini to the pot and cook over medium-low heat, stirring occasionally, until it starts to soften, about 15 minutes. Remove from the heat and add the broth, water, salt, and pepper to taste. Bring to boil, then reduce heat to low and simmer until the liquid is reduced by half and the vegetables are tender, 30 minutes to 1 hour. Serve with sour cream and Parmesan cheese.