Italian Marche Salt Cod with Potatoes | Baccalà con Patate alla Marchigiana

Sep 23

11 min read

Baccalà con Patate alla Marchigiana (Italian Marche Salt Cod with Potatoes)

This is a potato dish that happens to contain salt cod. The cod supplies salt, gelatin and large white flakes, but what reaches the fork loaded with flavour is the potato, because the potato spends the whole cooking time sitting in the fondo and drinking it. Olive oil, onion, tomato, wine and the brine leaving the fish all end up inside the tuber.

So the recipe turns on three decisions that have nothing to do with the fish. The variety: a yellow fleshed potato that holds its edges through forty minutes in liquid, never a floury one that surrenders and turns the pan grey. The cut, thick enough to survive and thin enough to absorb. And the layering, because in the Marche this goes into a wide tegame in strata, potato below, cod between, potato above, and it is never stirred.

What you want at the end is a pan where the sauce has almost disappeared into the vegetable, leaving a shallow glossy fondo thickened by starch rather than flour.

Yield: 6 servings. Prep: 30 minutes, plus 36 hours desalting if starting from dry salt cod. Cook: 55 minutes. Rest: 10 minutes. Difficulty: intermediate. Course: main course. Region: Marche, the Apennine foothills and the Adriatic coast.

The Story

Salt cod reached the Marche through the Adriatic ports and stayed because it solved a real problem. Ancona and San Benedetto del Tronto handled the northern fish that came down the Venetian trade routes from the Lofoten islands, and from those quays it went inland on carts to villages forty miles from the sea that might as well have been four hundred. Fresh fish could not make that journey in summer. A salted plank of cod could make it in any season.

The potato arrived much later and from the opposite direction, reaching the Apennines in the nineteenth century and settling on the high plateaus where wheat struggled. The plain of Colfiorito, on the border the Marche shares with Umbria, became one of the serious potato growing places of central Italy, and its red skinned highland potato is still the one local cooks reach for.

What held the two together was the calendar. Salt cod was the food of the vigilia and of the lean days of Lent, and potatoes made the pan feed six instead of three. The wide earthenware tegame went into the embers of the kitchen fire, the layers were built once and left alone, and the cook went back to work.

Ingredients

For the salt cod

Dry salt cod, thick loin, 2 1/4 lb (1 kg) before soaking, or 1 3/4 lb (800 g) desalted
Cold water for soaking, changed 5 or 6 times
Fresh bay leaf, 1, for the soaking water on the final change

For the potatoes

Yellow fleshed waxy potatoes, Yukon Gold or a firm highland variety, 2 lb (900 g)
Fine sea salt, 1/2 tsp (3 g), for the potato layers only
Freshly ground black pepper, 1/2 tsp

For the base

Extra virgin olive oil, 1/3 cup (80 ml)
Yellow onion, thinly sliced, 1 large, about 8 oz (225 g)
Garlic cloves, lightly crushed, 3
Peeled plum tomatoes, hand crushed and drained, 1 cup (240 g)
Dry white wine, 3/4 cup (180 ml)
Light fish stock or water, 1 cup (240 ml)
Fresh rosemary, 1 small sprig
Fresh flat leaf parsley stems, 5
Bay leaf, 1

For finishing

Flat leaf parsley, roughly chopped, 1/3 cup (15 g)
Extra virgin olive oil, 2 tbsp (30 ml), raw
Lemon zest, finely grated, from 1/2 lemon, optional
Freshly ground black pepper, to taste

Preparation

Step 1

Desalt the cod and then test it. Rinse off the surface salt, then submerge the pieces in cold water, skin side up so the salt falls away instead of settling back onto the flesh. Refrigerate 36 hours, changing the water five or six times. Poach a small trimming and eat it: if it is pleasantly seasoned the cod is ready, if it still bites give it another six hours. Pat very dry and cut into six portions of similar thickness, skin left on.

Step 2

Choose and cut the potatoes. Peel them and cut rounds a scant 1/2 inch (1 cm) thick. Thinner and they collapse into the fondo before the cod is cooked, thicker and the centres stay bland. Do not rinse the slices: that film of surface starch is what thickens the liquid at the bottom of the pan. Hold them uncovered and use them within twenty minutes.

Step 3

Build the base in the tegame. Set a wide shallow earthenware or heavy cast iron pan of 11 to 12 inches (28 to 30 cm) over medium low heat and add the oil. Cook the sliced onion with a pinch of salt for 10 to 12 minutes, until soft and translucent with no colour at all. Browned onion turns sweet and assertive, and this dish wants it in the background. Add the garlic, rosemary, bay and parsley stems for one minute.

Step 4

Cook out the tomato and the wine. Add the hand crushed tomatoes, drained of most of their juice so you are adding flavour rather than water, and cook over medium heat for 5 minutes until the oil separates at the edges. Pour in the wine and reduce it by half, about 3 minutes. What remains should taste finished on its own. Add no salt at this stage, because the cod has not yet released its own.

Step 5

Layer the pan. Off the heat, spread the base evenly across the bottom. Lay down half the potato in one overlapping layer, seasoned with pepper and a very little of the fine salt. Set the six cod portions on top, skin side down, spaced so they do not touch. Cover with the remaining potato, again overlapping, and season the same way. From here nothing gets stirred, and the only move allowed is a gentle shake of the pan by its handles.

Step 6

Add the liquid and give it the long stage. Pour the stock down the side of the pan rather than over the top, so the seasoning on the upper potatoes stays where you put it. It should come two thirds of the way up the layers and no higher. Bring to a bare simmer, drop to low, cover with the lid slightly ajar and cook for 30 minutes. Check twice by tilting the pan, and top up in tablespoons rather than cupfuls.

Step 7

Uncover and let the fondo concentrate. Cook a further 12 to 18 minutes, until a knife slides through the top potatoes without resistance and the liquid has reduced to a glossy fondo that clings to a spoon. This is where the potato starch does its work and the sauce thickens without anything being added. Shake the pan every few minutes to stop the bottom catching. The cod is now cooked through, insulated the whole time between two layers of potato.

Step 8

Season at the end and rest. Only now taste the fondo and decide about salt: depending on the desalting, many pans need none. Remove the rosemary, bay and parsley stems. Scatter over the parsley, grind on pepper and pour the raw oil across the top. Let the pan stand off the heat for 10 minutes, while the layers settle, the fondo tightens and the potatoes draw in the last of the liquid.

Plating

Serve this from the pan it was cooked in whenever you can. The tegame on the table is practical rather than sentimental: the layers are fragile and every transfer costs you one. Use a wide flat fish slice, which can reach the bottom of the pan and come up carrying the whole stack in one movement.

For a plated service, warm the plates: potato loses heat fast and this is one of the few dishes that genuinely needs hot china. Slide the slice under one cod portion with potato above and below and set it down without flipping it. Spoon the fondo around the base, never over the top.

Finish with parsley, a thread of raw olive oil and, if you like, a little grated lemon zest, which lifts the salt without adding acidity to a dish that already has tomato and wine in it. A bowl of bitter chicory dressed with oil is the traditional accompaniment, and it works because it contrasts rather than competes.

Professional Technique

The governing technique is stratified braising, and it exists because the two main ingredients want opposite things. Potato needs forty to fifty minutes in liquid to become tender through. Salt cod needs eight to twelve, and past that it contracts, expels water and goes stringy. The Marche solution is to bury the cod between two layers of potato so it never touches the heat of the pan base, and to let the potato insulate it throughout.

Inside that sandwich the cod sits well below the simmer point of the surrounding liquid. It cooks by conduction through wet starch, slowly and evenly, and arrives at the right point at roughly the same moment the potatoes do. It cannot dry out, because every surface is pressed against something full of water. That is why the instruction not to stir is the most important rule here.

The second technique is thickening by starch migration rather than by roux. Unwashed slices shed amylose into the liquid across the first twenty minutes, and as the fondo reduces uncovered that starch sets the sauce into something that coats, glossier and cleaner than flour ever gives.

Texture and Moisture Control

Waxy and floury potatoes behave in completely different ways here, and the choice is not a preference. Waxy varieties are low in dry matter and the pectin between their cells is slower to break down, so a slice survives forty minutes of braising with its edges intact and its interior creamy. A floury potato has larger starch granules that swell and burst, the cells separate, and the slice disintegrates into the fondo.

Moisture inside the cod is controlled by the desalting and by the gelatin. Cod soaked properly has reabsorbed a great deal of water, and the residual salt in the muscle helps it hold that water during cooking, exactly as a brine would. A slightly underdesalted piece stays juicier than one soaked to blandness. The skin, left on, holds the portion together and releases collagen into the fondo.

The last variable is the liquid level. Too much and the top layer boils rather than steams and the fondo never concentrates. Too little and the bottom layer catches. Two thirds of the way up is the target at the start, and by the end the liquid should be a shallow pool no deeper than a quarter inch. Judge it by tilting the pan, never with a spoon in the layers.

Professional Mise en Place

The difficulty here is scheduling rather than skill: the desalting runs for a day and a half, and the pan then runs almost unattended for an hour.

Equipment and tools

Wide shallow earthenware tegame or heavy cast iron pan, 11 to 12 inches (28 to 30 cm), with a lid
Deep container for soaking, holding the cod fully submerged in the refrigerator
Sharp knife or mandoline for even rounds of a scant 1/2 inch (1 cm)
Wide flat fish slice long enough to reach the bottom of the pan
Small saucepan for warming the stock before it goes into the pan

Prepared ahead

Cod desalted over 36 hours, dried and portioned, up to 1 day before cooking
A trimming poached and tasted to confirm the salt
Onion base with tomato and wine, cooked and cooled, up to 2 days ahead
Fish stock measured out and kept warm
Parsley chopped no more than an hour before service

Service setup

Potatoes cut at the last moment, unrinsed
Pan assembled once and never disturbed except by shaking it
Plates warmed
Finishing oil, lemon zest and pepper mill beside the pan
A ten minute rest built into the timing

Chef Tips

Buy the thick central loin and refuse the tail. The tail desalts faster, cooks faster and flakes into shreds, and in a pan where everything cooks for the same time it is dry long before the loin is ready. If you must take a whole side, soak the pieces separately by thickness.

Weigh your potatoes after peeling. The ratio that makes this work is roughly equal weights of desalted cod and peeled potato, and thick skinned highland potatoes can lose a fifth of their weight on the board.

Taste the fondo before you touch the salt cellar, then taste a potato from the top layer as well. The two will not taste the same. The fondo is where the cod brine collects and is always saltier than the potato above it, so seasoning on the sauce alone is how this dish ends up inedible. Judge on the potato.

If you can only find a semi waxy potato, cut the slices a full 1/2 inch and take five minutes off the covered stage. That buys back most of the margin you lose to the variety. Never compensate by lowering the liquid, which only pushes the bottom layer towards catching.

Common Mistakes

Using a floury baking potato. Russet and similar high starch varieties break apart within half an hour of braising, and once gone there is no recovery. Use a firm yellow fleshed waxy potato, and if unsure simmer one slice for twenty minutes before committing the pan.

Rinsing the cut potato slices. The surface starch is the thickener for the entire dish. Wash it down the sink and the fondo stays watery however long you reduce it, and the next mistake is usually flour, which dulls everything.

Stirring the pan. One pass with a spoon breaks the layers, exposes the cod to the direct heat of the base, and turns a stratified braise into a stew. If the pan needs attention, lift it and shake it by the handles.

Salting before the cod has released its brine. Desalted cod still carries a great deal of salt and gives it up steadily across the whole cooking time. Every seasoning decision belongs at the end, and many pans need no added salt at all.

Wine Pairing

Verdicchio di Matelica DOC: The Marche white to reach for, and specifically the inland one rather than its better known coastal cousin. Matelica sits in a closed valley whose wide temperature swings leave the wine tighter, more saline and more structured. That structure is what a pan of starchy potato and olive oil needs, and its bitter almond finish answers the salt in the cod.

Lugana DOC: Grown on the heavy clays south of Lake Garda, Lugana has a weight and a faintly waxy texture most northern whites lack, and weight is the requirement against a dish thickened with potato starch. Its acidity is moderate rather than piercing, which suits a preparation with no lemon and little tomato.

Greco di Tufo DOCG: A wine with unusual grip for a white, from the sulphur rich volcanic soils inland from Naples. It handles salinity in food better than almost any other Italian white because it brings its own, and its smoky stone fruit weight holds its shape against the olive oil. Serve it around 54°F (12°C).

Collio Friulano DOC: Friulano from the hills on the Slovenian border is broad and low in obvious aromatics, with a savoury almond finish that behaves almost like a seasoning. Against a dish whose dominant flavours are starch, oil and brine it supplies texture and length without adding a competing fruit character.

Trento DOC: The alpine metodo classico, and the choice when the pan goes to the table as a shared dish. Long lees ageing gives it a bready depth that meets the potato directly, while the mousse and mountain acidity scour the olive oil off the palate between forkfuls.

Storage & Reheating

This dish is better on the second day, and the reason is the potato: left overnight the slices keep absorbing the fondo and the salt distributes evenly through the layers. Cool it within two hours, cover the pan or transfer it whole to a shallow airtight container, and refrigerate up to 3 days.

Reheat it in a low oven rather than on the stovetop. Set the covered pan into a 300°F (150°C) oven for 20 to 25 minutes, adding 2 tablespoons of water if the fondo has set firm. Direct heat from below dries the bottom layer, and the microwave turns the cod to rubber while leaving the potato cold. Add fresh raw oil and parsley afterwards.

Do not freeze it. Braised potato loses its cell structure on thawing and comes back mealy and grey, and the cod, already once preserved and once rehydrated, turns fibrous. If you know you will not finish the pan, freeze the base alone for up to 2 months and assemble a smaller pan with fresh potatoes later.

Nutrition

Per serving, based on 6 servings:

Calories: 430 kcal
Total Fat: 16 g
Saturated Fat: 2.4 g
Trans Fat: 0 g
Unsaturated Fat: 13 g
Cholesterol: 75 mg
Sodium: 980 mg
Total Carbohydrates: 31 g
Fiber: 3.5 g
Total Sugars: 3 g
Added Sugars: 0 g
Protein: 36 g
Lactose: 0 g
Principal micronutrients: potassium, vitamin C, vitamin B12, iodine, selenium, phosphorus, niacin