Preheat the oven to 375°. Season the fish with salt and pepper and dust lightly with the flour.
In a medium ovenproof skillet, heat 1 tablespoon of the olive oil until shimmering. Add the fish and cook over high heat until golden on the bottom, about 4 minutes. Flip the fish. Transfer the skillet to the oven and roast the fish for about 10 minutes, until the flesh flakes with a fork. Transfer the fish to bowls.
Meanwhile, in another large skillet, heat the remaining 1 tablespoon of olive oil until shimmering. Add the garlic and cockles and cook over high heat for 1 minute. Add the wine and cook, stirring, for 1 minute. Add the clam broth and cook, stirring, until the cockles open and the liquid is reduced to about 1/4 cup, about 7 minutes. Tilt the skillet so the liquid pools to one side. Add the butter to the skillet and swirl until melted. Toss the cockles in the sauce and add the parsley; spoon them over the fish, sprinkle with smoked paprika and serve.