Here’s a seafood casserole that isn’t heavy or gloppy in the least. Based on a traditional Portuguese dish, it layers onion, white fish, potatoes, and tomatoes in a white wine broth–a symphony of harmonious flavors.
1/2 cup olive oil
4 large onions, sliced
2 large cloves garlic, minced
1/2 bunch fresh parsley, minced
2 teaspoons kosher or sea salt, divided
1/2 teaspoon freshly ground black pepper
1 teaspoon whole coriander seeds or 1/2 teaspoon ground coriander seed
2 pounds white fish, such haddock, flounder, or halibut
6 medium russet potatoes, peeled and sliced 1/4 inch thick
1 28-ounce can diced tomatoes
1 bay leaf
1 cup dry white wine, such as Pinot Grigio
Set a 4- to 5-quart heavy-bottomed pot over medium heat. Add the oil. When sizzling, add the onions, garlic, parsley, 1 teaspoon salt, pepper, and coriander. Cook, stirring occasionally, until the onions are golden, 10 to 12 minutes.
Place the fish in an even layer over the onions, then add the potatoes, tomatoes, bay leaf, remaining 1 teaspoon salt, and wine. Cover tightly, reduce heat to low, and gently simmer until the potatoes are done and the fish is cooked through, 35 to 45 minutes.