Chopped eggplant and mushrooms give a rich flavor and meaty texture to this Mediterranean-style vegetable dish. Serve it with some steamed or boiled rice for a well-balanced meal.
In a Dutch oven, heat oil over medium heat. Add onion, garlic, eggplant, mushrooms, 2 teaspoons salt, and 1/4 teaspoon pepper. Cook, stirring occasionally, until eggplant begins to brown, 5 to 10 minutes.
Add zucchini, water, and tomato puree, and bring to a boil. Reduce heat to medium-low, cover, and cook until eggplant is tender, about 20 minutes. Stir in beans, vinegar, and parsley, and cook just until heated through, about 5 minutes.
To help this squash cook evenly, cut it into uniform pieces; first slice the zucchini in half lengthwise. Then slice each half crosswise. For attractive half-moons, cut on a slight diagonal.