Pistachio-crusted barramundi with roast tomatoes and broccoli

Sweet, white fillets of prime Humpty Doo barra, coated in a vibrant pistachio, preserved lemon and caper crust, with roast baby tomatoes and broccoli dressed in a lemony vinaigrette. The crust protects the delicate fish as it cooks and elevates this simple one-tray wonder into something that punches well above its weight. A potato gratin or mash on the side would do nicely, thanks.