Cut striped bass fillets and halibut fillets into 2-inch cubes (don't use tuna or salmon — they do not belong in a fish stew).
In a large skillet, heat olive oil over medium-high heat. Add chopped shallots, chopped garlic, and dried crushed red pepper.
After they are light brown (about 2 minutes), add parsley, then quickly throw in the fish. Add salt and pepper to taste. After the fish is lightly coloured, add clams and mussels and white wine.
Cover the pan and cook over medium heat for 5 minutes (when the mussels and clams open, the stew is done). Sprinkle with chopped Italian parsley.
Serve with 1/2-inch-thick slices of Italian bread, fried in olive oil, on the side. That's it; it's done.