-
1
Score the fish lightly on both sides — two or three diagonal cuts reaching the bone — so that heat penetrates evenly. Season the cavity with salt.
-
2
Choose a wide, shallow pan in which the fish lies flat. Scatter the sliced garlic and tomatoes across the base. Lay the fish on top. Add the olive oil, the chilli if using, and the salted water — and the white wine if using — so that the liquid comes halfway up the fish, no further. Excess water will dilute the broth beyond recovery.
-
3
Set the pan over medium-high heat and bring the liquid to a lively simmer. Do not cover the pan. As soon as the liquid moves, begin spooning it continuously over the exposed upper flesh of the fish. This basting — sustained without interruption for the entire cooking time — is where the dish lives or dies: it is the act that fuses water, tomato, fish essence, and oil into a coherent broth while cooking the fish evenly from both sides.
-
4
Continue basting for 12 to 18 minutes, according to the weight of the fish. The broth will turn from watery to lightly emulsified, coloured faintly rose by the tomatoes. The fish is done when its flesh lifts cleanly from the bone at the thickest point behind the head and remains moist and pearlescent — not white and firm, which indicates overcooking.
-
5
Remove the pan from the heat immediately. Scatter the parsley over the fish and broth. Finish with a drizzle of raw extra-virgin olive oil directly into the broth. Serve at once in shallow bowls with bread for soaking. The broth, neither soup nor sauce, is as much the dish as the fish itself.