Italian Roasted Turbot with Brown Butter, Samphire and Celeriac | Rombo Chiodato con Burro Nocciola, Salicornia e Sedano Rapa
Turbot is the most expensive flat fish in the Adriatic and the least forgiving to overwork. This plate gives it three things and nothing else: celeriac purée for sweetness and body, salicornia for salt and snap, and brown butter for the roasted note a white fish cannot produce on its own. It is roasted on the bone, where turbot gives its best texture, and the butter is taken to the colour of a hazelnut and stopped there.
Everything turns on that butter. Thirty seconds too long and it stops being nutty and turns acrid, and no amount of lemon afterwards will pull it back. The rest of the plate stays quiet so the butter can be the loudest thing on it.
Yield: 2 servings. Prep: 30 minutes. Cook: 30 minutes. Rest: 6 minutes. Total: about 1 hour 10 minutes. Difficulty: advanced. Course: secondo di pesce. Region: northern Adriatic, the Venetian lagoon and the Po delta.
The Story
Rombo chiodato takes its Italian name from its skin. The dark upper side of Scophthalmus maximus is studded with hard bony tubercles, and chiodato means studded with nails. It lies flat on sandy and muddy bottoms from the northern Adriatic down the Tyrrhenian coast, ambushing whatever swims past, and it has been the single most prized flat fish of the Italian table for as long as records exist. In Venice and Chioggia it was the fish bought for Christmas Eve and for weddings, and on the Romagna coast it still carries a price no other local catch approaches.
Salicornia grows where the turbot is landed. The salt marshes of the Venetian lagoon, the barene, and the brackish flats of the Po delta and Comacchio produce it through spring and early summer, and the fishing families who worked the lagoon have always eaten it: free, abundant, and so saline that it needs no salt added to it at any point. Venetians call it asparago di mare. It is one of the few wild greens in Italy that is still gathered rather than farmed on any scale.
The butter is the northern half of the story. Italy is usually described as a country of olive oil, but the Po valley, Lombardy and the Alpine provinces are dairy country and have cooked in butter for centuries, long before French technique gave the browned version a name. Sedano rapa belongs to the same latitude, a winter root of Friuli, Veneto and Trentino that arrived from central Europe and stayed. Put together, the plate is entirely northern: a lagoon fish, a lagoon weed, a mountain root and a Po valley fat.
Ingredients
For the turbot
Turbot, whole, gutted and trimmed, 2 1/4 lb (1 kg), or two bone in portions of 9 oz (255 g)
Fine sea salt, 1 tsp (6 g)
Extra virgin olive oil, 1 tbsp (15 ml)
Unsalted butter, 1 tbsp (14 g)
Freshly ground white pepper, to taste
For the celeriac puree
Celeriac, peeled and diced, 1 lb (450 g)
Whole milk, 3/4 cup (180 ml)
Unsalted butter, 2 tbsp (28 g)
Heavy cream, 2 tbsp (30 ml)
Fine sea salt, 1/2 tsp (3 g)
For the brown butter
Unsalted butter, cold, cut in cubes, 5 oz (140 g)
Lemon juice, 2 tsp (10 ml)
Small capers, rinsed, 1 tbsp (10 g)
For the samphire
Fresh salicornia, picked into short tips, 3 1/2 oz (100 g)
Unsalted water, for blanching, 4 cups (950 ml)
Ice water, for refreshing
For finishing
Finely grated lemon zest, from 1/2 lemon
Flat leaf parsley leaves, small, 8
Extra virgin olive oil, a few drops per plate
Flaky sea salt, for the fish only, a small pinch
Preparation
Step 1
Portion the turbot and keep it on the bone. If you have a whole fish, cut it across the backbone into two thick bone in tranches and reserve the frame. Do not fillet it. Turbot bones are broad, gelatinous and slow to heat, and the flesh against them stays moist while the rest cooks. Salt the fish lightly on both sides and leave it uncovered on a rack in the refrigerator for 20 minutes so the surface dries.
Step 2
Cook the celeriac in milk, not water. Put the diced celeriac in a small saucepan with the milk, 1 tablespoon of the butter and the salt, cover, and cook at a bare simmer for 18 to 20 minutes until a knife slides through with no resistance. The milk should be almost gone. Water leaches the flavour out and gives a thin purée; milk holds it and supplies the body.
Step 3
Blend and strain the puree. Transfer the celeriac and whatever milk remains to a blender, add the remaining butter and the cream, and blend until completely smooth. Pass it through a fine mesh sieve. Adjust the salt now, while it is hot. Hold it warm and covered, and loosen it with a spoonful of hot milk if it tightens.
Step 4
Blanch the salicornia in unsalted water. Bring the water to a rolling boil with no salt at all, drop the tips in for 30 to 40 seconds, then lift them straight into ice water. Salicornia carries its own salt and any added to the pot makes it inedible. Drain it thoroughly and keep it at room temperature; warming it again costs the snap that is its contribution.
Step 5
Roast the fish. Heat the oven to 400°F (200°C). Get an ovenproof pan hot over medium high heat, add the olive oil, and lay the tranches down dark skin first. Give them 2 minutes without moving them, add the tablespoon of butter, turn the fish, then move the pan to the oven for 7 to 9 minutes. Baste once halfway through.
Step 6
Check the temperature at the bone and rest the fish. Push a thin probe into the thickest part, against the bone but not touching it: you want 122°F (50°C). The flesh should lift away in one piece and look pearly rather than white. Transfer the fish to a warm plate and rest it for 5 to 6 minutes. It climbs another 4 or 5 degrees off the heat.
Step 7
Make the brown butter last. Melt the cold cubed butter in a light coloured stainless pan over medium heat and let it foam. When the foaming dies down and the solids on the bottom turn the colour of a hazelnut and the smell turns nutty, count to twenty and take it off the heat. Add the lemon juice at once, then the capers, and swirl. It is finished.
Plating
Use warm plates, wide and plain. Everything except the salicornia is served hot, and a cold plate pulls the butter below the temperature at which it stays fluid, turning a glossy sauce into a greasy film in under a minute.
Spoon two generous tablespoons of celeriac purée slightly off centre and pull it into an oval with the back of the spoon in one movement. Lift the tranche off its bone in a single piece if it comes cleanly, or leave it on the bone, which is how it is eaten on the Adriatic. Set it partly over the purée.
Pile the salicornia loosely beside the fish, never on top of it. Spoon the brown butter and the capers over and around the fish so it pools against the purée, and finish with the lemon zest, the parsley, a few drops of olive oil and a small pinch of flaky salt on the fish alone. The salicornia and the butter are salted enough already.
Professional Technique
Everything technical about this dish is in the butter, so it is worth knowing what butter actually is. Butter is not a fat: it is an emulsion of roughly 80 to 82 percent fat, 16 to 18 percent water, and 1 to 2 percent milk solids, which are milk proteins and lactose. Beurre noisette is a sequence in three acts, each driven by one of those three components.
First the water leaves. The butter melts, then foams violently as the water boils off, and the foaming is the visible sign that it is still happening. When the foam subsides the water is gone and the pan can climb past the boiling point of water. Second, the milk solids, now dry, fall to the bottom and begin to brown. This is the Maillard reaction between the milk proteins and the lactose, and it produces the hazelnut, toffee and toasted note that gives the preparation its name. Third, those same solids burn, going from brown to black and from nutty to acridly bitter, and that third act takes twenty or thirty seconds after the second one ends.
Three consequences follow. Use a light coloured stainless pan, because in black cast iron you cannot read the colour of the solids and colour is the only reliable signal you have. Stop the reaction with acid the moment the colour is right: 2 teaspoons of lemon juice drops the temperature, halts the browning instantly, and seasons the sauce at the same time. And decide whether the solids stay or go. Strained through muslin you get a clear nutty fat; left in, as here, they give texture and a deeper roasted flavour.
That last choice suits this fish. Turbot has a broad skeleton rich in collagen, which is why it cooks better on the bone than off it, and flesh firm enough to carry a browned fat that would smother sole. The salicornia is the counterweight and needs none of this: it is already as salty as anything you could season it with.
Texture and Moisture Control
Turbot is done at 122°F (50°C) at the bone and ruined at 140°F (60°C). In that window the flesh is pearly and translucent at the centre and separates into thick moist flakes; past it the muscle proteins contract, squeeze out their water and leave the fish chalky. Because the bone conducts heat slowly and keeps releasing it, pull the pan at 122°F and let the rest carry it to the finish.
The collagen in those broad flat bones melts into gelatin and coats the flesh nearest them, which is why the piece against the bone is always the best on the plate and why a fillet never eats the same way. The juices it releases are worth spooning into the brown butter at the end.
The purée and the salicornia fail in opposite directions. A purée cooked in water or loosened with too much cream turns loose and weeps a ring onto the plate; cooked down in milk and strained, it holds its shape without setting. Salicornia held past 40 seconds, or reheated at service, goes limp and khaki, and limp salicornia has nothing left to give the dish.
Professional Mise en Place
Only the roasting and the butter are à la minute, and the butter cannot be made in advance under any circumstances, so everything else is finished and holding before the fish goes into the pan.
Equipment and tools
Light coloured stainless saucepan for the butter, never black cast iron
Ovenproof sauté pan wide enough to hold both tranches without crowding
Blender and a fine mesh conical sieve
Instant read probe thermometer, thin tipped
Fish spatula and a spoon for basting
Prepared ahead
Celeriac purée, blended and strained, up to 1 day ahead, refrigerated
Salicornia blanched, refreshed and drained, up to 4 hours ahead
Turbot portioned, salted and drying uncovered on a rack, 20 minutes ahead
Lemon juiced and zested, capers rinsed, butter cubed and cold
Service setup
Oven at 400°F (200°C) and fully preheated, plates warming
Purée warm and covered, with hot milk within reach to loosen it
Butter pan clean, dry and empty on the second burner
Probe, spatula and garnishes lined up before the fish is laid down
Chef Tips
Buy the fish whole and have the fishmonger cut it across the bone in front of you. A turbot sold as fillets is usually a small one, and the bones you lose are most of what you are paying for.
Start the butter cold and cubed rather than as one warm block. Cubes melt evenly and the whole pan reaches the foaming stage together, so the solids brown at one rate instead of scorching in the middle while the edges still release water.
Taste the salicornia raw before seasoning anything else on the plate. Its salinity varies enormously with where and when it was picked, and on a very salty batch you should drop the flaky salt at the finish altogether.
Keep the pan juices from the fish and tip them into the brown butter with the capers. They carry gelatin from the bone, which gives the sauce more body and stops it sliding straight off the fish.
Common Mistakes
Salting the water for the salicornia. It grows in seawater and is already saline enough to be a seasoning in its own right. Boiled in salted water it comes out inedible, and there is no correcting it afterwards.
Walking away from the butter. The window between properly nutty and irreversibly burnt is twenty to thirty seconds. Stand over the pan, watch the colour of the solids, and have the lemon juice measured out before you start.
Filleting the turbot before roasting. Off the bone it loses the gelatin that keeps it moist and overcooks in half the time. Cut it into bone in tranches and let the diner work around the bone, as they would on the Adriatic.
Cooking the celeriac in water. Water pulls the flavour into the pan and gives a purée that tastes washed and weeps on the plate. Cook it covered in milk until the liquid has nearly gone, then blend that liquid back in.
Using a black pan for the butter. In cast iron the browning solids are invisible until they smell wrong, by which point they are bitter. Colour is the signal, so use a pan you can read it in.
Wine Pairing
Franciacorta DOCG: The most complete match here, and from the same butter country as the dish. Long lees ageing gives bread crust and toasted hazelnut aromas that run alongside the browned milk solids, while the pressure and the high acidity scrub the butter fat off the palate between mouthfuls. Choose a Brut rather than a Satèn: the fuller bubble works harder against the fat.
Verdicchio dei Castelli di Jesi Classico Riserva DOCG: The Riserva has the weight to sit under a rich fish without being pushed aside. Its bitter almond finish picks up the nutty half of the butter, the marked acidity keeps the celeriac cream from turning heavy, and bottle age gives it a waxy texture close to the flesh of the turbot.
Vermentino di Gallura DOCG: Grown on decomposed granite, it carries a saline bite and a firm citrus acidity that meets the salt of the salicornia on equal terms instead of being flattened by it. There is texture enough to carry the butter, and a faintly bitter finish that stops the plate reading sweet against the celeriac.
Fiano di Avellino DOCG: Hazelnut and beeswax on the nose mirror the beurre noisette almost literally, and the low yields of the Irpinia hills give real body. Its acidity is quieter than the northern whites, so pour it when the celeriac dominates rather than the salicornia.
Etna Bianco DOC: Carricante from volcanic sand, with cutting acidity and a smoky saline edge that works on the roasted surface of the fish rather than against it. It is the leanest bottle here, so it suits a generous hand with the butter and can read austere on a restrained plate.
Storage & Reheating
Store the components, never the assembled plate. The celeriac purée holds in an airtight container in the refrigerator for 3 days and freezes for 2 months; rewarm it over low heat with a spoonful of milk, stirring, and it comes back as it was. Blanched salicornia keeps refrigerated in a sealed box for 2 days and is eaten cold.
Brown butter keeps refrigerated for up to 2 weeks and sets solid. Rewarm it over the lowest heat until just fluid and never let it simmer again, which drives the browning further and turns it bitter. Make it fresh when you can: it takes four minutes.
Cooked turbot is best eaten at once. If you have leftovers, keep them on the bone, covered, for up to 1 day, and bring them back in a 275°F (135°C) oven for 6 to 8 minutes rather than a pan or a microwave, both of which cook the fish twice. Do not freeze cooked turbot.
Nutrition
Per serving, based on 2 main course portions:
Calories: 810 kcal
Total Fat: 62 g
Saturated Fat: 36 g
Trans Fat: 2 g
Unsaturated Fat: 22 g
Cholesterol: 245 mg
Sodium: 1150 mg
Total Carbohydrates: 18 g
Fiber: 4 g
Total Sugars: 9 g
Added Sugars: 0 g
Protein: 48 g
Lactose: 4 g
Principal micronutrients: iodine, selenium, vitamin B12, vitamin A, potassium, phosphorus
These figures are estimates. The fat is high because the butter is the sauce, and the sodium depends almost entirely on the salicornia, which varies batch by batch and is the reason no salt is added to its water.
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