I tend to call this fishbread.... it's very very good and not hard despite looking impressive. From Pepin's Celebrates book

When I'm lazy, I just prepare bread and crumbs, as he says, then make herb butter of just butter, parsley and shallots. Layer chopped salmon, scallops and shrimp with butter and bread crumbs, and bake. I think it would work with just fish as well, or just shellfish.

SEAFOOD BREAD


I use a large, round country-bread loaf for this recipe, but baguettes or individual rolls also can be used as receptacles for the delicious seafood mixture. The entire seafood bread can be assembled up to a day ahead and kept in the refrigerator, ready to be cooked in the oven.

INGREDIANTS

1 large, round country-bread loaf (about 1 1/2 pounds, and 11 to 12 inches in diameter), either homemade or store-bought
GARLIC-HERB BUTTER
1/2 cup parsley
1/2 cup herbs (a mixture of basil, chives, and chervil)
3 large cloves garlic
3 tablespoons pecan halves
1 1/2 sticks unsalted butter, softened
1/2 teaspoon salt
1/2 teaspoon freshly ground black pepper
2 tablespoons dry white wine
2 shallots, peeled and finely chopped (1/3 cup)
1/2 pound shrimp, shelled
1/2 pound sea scallops
1/2 pound salmon, boneless and skinless
1/2 pound wild or white cultivated mushrooms
Salt and freshly ground black pepper to taste
A cup dry white vermouth

Preheat the oven to 400 degrees. Using a sharp knife, cut all around the top of the bread loaf, and remove the top or "lid" of the bread, exposing the crumb beneath. Set this "lid" aside, to eat or use in another recipe. Then, measuring in about 3/4 inch from the edge of the loaf, cut down into and all around the loaf, taking care not to penetrate the bottom, to create a neat edge from which to remove the interior crumb. Twist the soft insides to loosen them, then pull them out, so you have a large receptacle or shell.
If the insides of the bread are very soft, cut them into pieces and dry them briefly in the hot oven. Then place about half of the insides into the bowl of a food processor, and process to make 2 1/2 to 3 cups of crumbs. Set these aside, and keep the remainder of the bread insides for another use.
For the garlic-herb butter: Put the parsley, other herbs, and garlic in the food-processor bowl, and process until the mixture is chopped fine. Add the pecans, softened butter, salt, pepper, and white wine, and process until
blended. Stir in the shallots. Using a large spatula, coat the inside of the hollow loaf with about a third of the garlic-herb butter.
Cut the shrimp, scallops, and salmon into 1-inch pieces, and slice the mushrooms. Sprinkle half the mushrooms and half the seafood into the bread receptacle, and sprinkle lightly with salt and pepper.
Add a layer of the garlic-herb butter, then about half of the breadcrumbs, and the remainder of the seafood and mushrooms. Season lightly with salt and pepper. Finally, spread the remaining butter on top, cover with the remaining breadcrumbs, and moisten the breadcrumbs with the vermouth. Place the filled bread loaf on a cookie sheet, and bake for about 1 hour. (Note: It does need that amount of cooking, so if the bread loaf you are using has a very dark crust and you don't want it to brown much more, wrap the bottom and sides of the loaf in aluminum foil before placing the bread in the oven.)
Let the bread rest for 10 minutes after it comes out of the oven, then cut it into large chunks, and serve immediately.