1. Heat the oil in a large, shallow flameproof casserole over medium-low heat. Add the onion and leek and cook, stirring often, about 5 minutes, until tender.

2. Stir in the tomatoes and garlic and cook for 2 minutes. Add the potatoes, saffron, and bay leaves, and season well with salt and pepper.

3. Place the salt cod, skin side up, on the vegetables. Pour in the wine and 1 cup water. Bring to a simmer. Cook, shaking the casserole every 5 minutes or so to release gelatin from the fish to thicken the sauce, for about 25 minutes, or until the potatoes are tender.

4. Sprinkle with parsley and serve hot, from the casserole.