This easy zuppa di pesce is a staple of the anchovy packers of Mazara del Vallo on the northwestern coast of Sicily. It always comes with bread to soak up the juices.
Heat olive oil in heavy large pot or Dutch oven over medium-high heat. Add chopped onion and garlic and sauté 4 minutes. Add parsley and stir 2 minutes. Add tomato and cook 2 minutes longer. Add 1 1/3 cups cold water and dry white wine and simmer until fish is cooked through, about 10 minutes. Season stew to taste with salt and pepper. Ladle into bowls and serve.