'Nduja

'Nduja is a cured raw pork sausage from Calabria, the toe of Italy. It is made from fatty cuts (belly, jowl, back fat, trimmings) ground very fine and worked together with dried, milled Calabrian chilli and salt, then stuffed into a natural casing, lightly smoked and aged for three to six months.

The chilli content is what makes it unlike anything else in the Italian salumi cabinet: between a quarter and 40% of the mix. That is not seasoning, it is a structural ingredient. The capsaicin acts as a preservative, which is the only reason a paste this fatty can be cured at all.

Because of the fat and the fine grind, it does not slice. At room temperature it has the consistency of a firm pâté and spreads with a knife. Warm it and it dissolves completely into a red, oily, extremely spicy liquid, which is how most restaurant kitchens use it.

It carries Italy's PAT designation (a traditional-product register) but no DOP or IGP, so the name is legally open. Quality varies wildly as a result.

Fire first, then pork. The heat arrives immediately and builds for several seconds: clean and bright rather than the slow burn of a habanero, and it fades faster than you expect. Behind it is deep, sweet, almost funky cured pork fat, plus a distinct smokiness from the brief wood smoking.

The chilli itself is a big part of the flavour, not just the heat. Calabrian peperoncino is fruity and slightly sweet when dried, closer to a good ancho than to cayenne, so 'nduja tastes of red pepper as much as of capsaicin.

On the Scoville scale a traditional Spilinga 'nduja lands somewhere in the jalapeño-to-serrano range overall, but because the fat carries the capsaicin it coats your mouth and reads hotter than the number suggests. Commercial versions sold in supermarkets are usually toned down considerably.

The simplest use is still the best: spread it thickly on warm bread or grilled bruschetta and let the heat of the toast soften it.

In cooking, treat it as a concentrated condiment rather than as a meat. A tablespoon melted in a pan over low heat with a splash of oil is enough to build a pasta sauce for two: the classic Calabrian combination is 'nduja and Tropea red onion, with or without tomato. Keep the heat low. Fry it hard and the chilli scorches and turns bitter.

It goes into scrambled eggs, stirred through braised greens, whisked into a vinaigrette, dropped into a bean or lentil soup, and folded into a meat ragù for depth. On pizza it goes on in small dabs in the last seconds of baking or immediately after the pizza comes out.

The pairing that has taken over restaurant menus in the last decade is 'nduja with fresh dairy (burrata, stracciatella, ricotta) where the cold sweet cream cuts the heat. It is not traditional and it works extremely well.

Whole in its casing and unopened, it sits in the fridge or a cool larder and carries a long date from the producer, since salting, fermentation and light smoking have already taken most of the free water out. Once you cut into it, the exposed face is what changes: within a few days it dries, darkens towards brown red and forms a firmer crust, so wrap the cut end in baking paper and then foil rather than pressing cling film against the meat. An opened jar goes in the fridge, always with a clean spoon; level the surface and let the released fat settle back over it, because air on the surface is what dries and dulls it.

Over weeks the fat oxidises and the smell turns sharper and less sweet, and light fades the red towards a dull rust, which is why jars keep better at the back of a shelf. It freezes well in portions, wrapped tightly; the texture stays spreadable after thawing because the fat content is so high. The producer date on the casing or lid is the reference.

The ingredient list is the fastest check: pork, Calabrian chilli, salt. Paprika, tomato, added oil, colouring or starch point to something built to look the part. The colour is brick to orange red, deep but never fluorescent. In a casing it feels firm from the fridge and turns spreadable within twenty minutes on the counter; in a jar the surface is smooth and a layer of clear rendered fat on top is normal. The smell is sweet roasted pepper with smoke behind it, not raw heat.

Abroad it is most often mixed up with sobrasada, the Mallorcan spreadable sausage, which is paprika based, paler orange and far milder, and with soft chorizo sold in the same chiller. Chilli pastes and harissa sit nearby and are not the same thing at all. Labels reading 'nduja flavoured or 'nduja style are usually sauces with a small percentage of it. Spilinga, in the province of Vibo Valentia, is the reference town and often appears on the label. Expect roughly $12 to $20 or £6 to £10 for 200g.

In the US, the standout domestic producer is 'Nduja Artisans Salumeria in Chicago, whose version is closer to the Calabrian original than most imports and is stocked by good cheese shops nationwide. Tempesta Artisan Salumi, Olympia Provisions and Creminelli also make one. For imports, Eataly, Gustiamo, Murray's Cheese and Formaggio Kitchen carry Calabrian producers. Expect $18 to $30 per pound, or $8 to $14 for a 7oz jar.

In the UK, 'nduja is unusually well distributed: Ocado, Waitrose, Sainsbury's and M&S all carry it, and the UK searches for it more than the US does in relative terms. For the real thing, Natoora, The Ham & Cheese Company, Vallebona and Delicatezza import from Calabria. Prices run £4 to £8 for a 200g jar, £25 to £40 per kilo for whole casings.

Buy the whole casing rather than the jar where you can. It costs less per kilo, keeps far longer because the surface stays protected, and it has not been pasteurised, which jarred versions usually are. Read the ingredients: pork, chilli, salt. Anything listing paprika, starch, beef or 'flavourings' has been stretched.

Spilinga, a village of about a thousand people in the province of Vibo Valentia, is the origin and still the best place to eat it. The Sagra della 'Nduja takes over the town every 8 August; the rest of the year the historic producers sell directly from their workshops.

The whole Monte Poro plateau (Ricadi, Joppolo, Zungri, Rombiolo) has serious production at producer prices. Tropea, twenty minutes away on the coast, is the practical base: it has the hotels, the beaches, the red onions and a 'nduja in every deli window.

Vibo Valentia and Pizzo have good salumerie in their old centres. Further north, Cosenza and the Sila highlands run on a different salumi tradition built around soppressata and capocollo, where 'nduja is present but not native.

Outside Italy, London has arguably the deepest 'nduja habit of any city (it turns up on pizza, on toast and in pasta across the city) and New York's Italian restaurants have adopted it wholesale.