How to cook the perfect clam chowder

http://www.theguardian.com/lifeandstyle/wordofmouth/2014/apr/10/how-to-cook-perfect-clam-chowder

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An honourable member of that clan of thick, comforting seafood soups whose other members include cullen skink, bisque and mohinga, the chowder is thought to be named after the iron cauldrons it was originally prepared in – the communal "chaudiere" which travelled to the east coast of the States along with French sailors.

Though the first chowder recipe doesn't put in an appearance until 1800, according to the Encyclopedia of American Food and Drink, by the middle of the century it was "a staple dish of New Englanders, and for sailors merely another another way to make a constant diet of fish palatable".

Although clam certainly wasn't the only, or even the most popular, variety in past centuries, it's the most famous today, with spin-offs including the tomato-based Manhattan clam chowder, the simple Rhode Island version and even a spicy habanero pepper variety from Florida. The classic New England chowder has long been distinguished by its use of dairy, and it's this so-called white chowder I'm attempting today. After all, everything's better with cream.

Clams

This proved the most difficult part of the whole endeavour – Americans are lucky enough to rejoice in an embarrassment of choice, but my three local fishmongers offer just one soft-shell variety (the razor) and one hard shell (the palourde). Chowder is generally made with hard-shell clams as, according to Cook's Illustrated's New Best Recipe book, they tend to be less gritty, but the enormous quahogs (4-5in across) and slightly smaller cherrystones in the US dwarf the diminutive palourde. Although these larger species are far more common in American waters, the Fish Society has some available from European colonies, which can be purchased online, but the more common smaller varieties will give just as good a flavour – it's just a shame to waste them on soup.

James Beard is the only writer to suggest steaming the clams in anything but water. He uses white wine, which is very nice (as fans of spaghetti alle vongole will attest), but gives his finished dish a rather Gallic flavour. Water does just fine – and not too much of it either, as the cooking liquor forms the base of the chowder.

Mark Bittman, writing in the New York Times, reminds readers to catch every last drop of juice when shucking the clams, and strains this through cheesecloth – a wise precaution, as even well-scrubbed clams will contain some grit.

Meat and veg

Salt pork was the original choice for chowder but, as Cook's Illustrated observes, "we ended up using such small amounts of pork in our final recipe that either [that] or bacon is fine". A good butcher or delicatessen should be able to get you salt pork (or you can make your own) if you hunger after the authentic taste of the eastern seaboard, but unsmoked, thick-cut bacon or pancetta will do the job just as well. Bittman leaves pork out altogether, and I'm disappointed – after the clams themselves, it's the key flavour of chowder, the rendered fat lending the broth a rich, savoury flavour.

Whichever kind you use, frying the pork until crisp and golden is important. You don't need to do it as slowly as the Cook's Illustrated recipe implies, but you should leave it in the pot to allow the flavours to mingle, rather than scooping it out and using it as a garnish, as in the Saveur magazine version.

Onions and potatoes are a must in a chowder. Yu should soften the potatoes in the soup itself, rather than separately like Beard, so they soak up all the wonderful clam juices as they cook. Cook's Illustrated and Saveur specify red potatoes, the former on the grounds that "their skins look appealing". Leaving skins is always a good idea flavourwise, and the contrast in colour certainly looks attractive in the bowl, but any waxy variety will do – the floury kind fall apart during cooking.

The New York Times Cookbook sneaks some sliced tomato in alongside the dairy in its recipe from 1881 (Manhattan by stealth), but it gives the chowder a more acidic, savoury edge that feels less comforting, somehow.

Broth

The clam cooking water forms the backbone of the soup, but everyone except Bittman adds dairy as well, which is vital for a real New England chowder. The New York Times's milk is too thin for my liking, though – as is Saveur's single cream and milk, which dilutes the soup so much it barely tastes of clams. Better to use less but thicker dairy, such as Cook's Illustrated's choice of double cream, stirred in at the end along with the clams.

Thickener

Not everyone uses a thickener in chowder (Beard and Bittman don't bother) but it is traditional, and gives the soup a bit more body – it shouldn't be thin or delicate, after all. The New York Times goes for the very traditional crackers, instead of flour – the now defunct Massachusetts pilot crackers, which, according to research online, are best substituted with Bath Olivers. Floated whole in the soup, they fail to soften sufficiently to dissolve into the broth, so even after some robust stirring I'm left with lots of soggy biscuit, which don't do much in the way of thickening and look distinctly unappetising. Flour it is.

Herbs and finishes

I'm not sure a chowder demands much in the way of herbs and spices – thyme and parsley are popular, and the New York Times uses marjoram, while Beard sprinkles his with paprika. The only one I think really complements the flavours is the Cook's Illustrated's bay leaf, along with plenty of black pepper.

Saveur finishes its chowder with a knob of butter, and if those 19th-century fishermen had had any to spare I bet they would have done the same – a little extra richness is just the thing to keep the miserable weather at bay.

The perfect clam chowder

(Serves 4)2kg fresh clams, scrubbed200g thick unsmoked bacon or pancetta, cut into small dice1 onion, finely chopped1 bay leaf2 tbsp plain flour2 medium waxy potatoes, chopped into 1cm dice150ml double creamKnob of butter

Put the clams in a large pan with 600ml water. Cover, bring to the boil and steam until most are open, then pour into a sieve with a bowl underneath to catch the cooking liquid.

When cool enough to handle, remove from their shells and discard these. Roughly chop the clams, if large. Strain the liquid through a couple of layers of paper towel, or cheesecloth – you should have about 1.2 litres.

Meanwhile, heat a medium pan over a medium-high heat and fry the bacon in its own fat until this begins to render. Add the onion and fry until this is soft, the bacon is crisp, and both are beginning to brown. Add the bay leaf and flour and cook, stirring, for a couple of minutes.

Slowly stir in the clam liquid, then add the potatoes. Simmer until these are tender (about 10 minutes), then stir in the cream, clams and butter. Heat through, season to taste with plenty of black pepper and salt if necessary, and serve.

Clam chowder: do you like yours New England, Manhattan or Minorcan style, or do you prefer fish or corn chowder, or another kind of seafood soup entirely? And, out of curiosity, does anyone know of any traditional British dishes using clams?