How to Make It
In a food processor, pulse the bread until coarse crumbs form. In a medium skillet, heat the olive oil until shimmering. Add the anchovy, garlic and crushed red pepper and cook over high heat, stirring, until the anchovy dissolves and the garlic is just beginning to brown, about 30 seconds. Stir in the bread crumbs and capers and cook over moderately low heat, stirring constantly, until the bread is golden and crisp, about 8 minutes. Off the heat, stir in the parsley and lemon zest and season the toasted bread crumbs with salt and pepper.
Meanwhile, lightly butter a 9-inch glass pie plate. Arrange the fish fillets skin side down in the plate. Season with salt and pepper and dot with the 4 teaspoons of butter. Place 2 lemon slices on each fillet and drizzle with the wine.
Make a steamer by arranging 3 small balls of aluminum foil in a very large, deep skillet. Add 1 inch of water to the skillet and bring to a boil. Carefully set the pie plate on the foil balls, cover the skillet with a tight-fitting lid or aluminum foil and steam the fish for about 8 minutes, until it flakes with a fork. (Alternatively, steam the fish in a shallow bowl set in a bamboo steamer.)
Using a spatula, transfer the sea bass fillets to shallow bowls and spoon the broth on top. Push the lemon slices off to the side and top the fillets with the toasted bread crumbs. Serve right away, before the crumbs get soggy.