Cod piece

The Danish Codfeast is the perfect dish for New Year

The normal topic central to New Year's Eve is not what you will eat but what you will drink, and how much. I think the Danish go in for this too - schnapps is no shrinking violet - but more important is the ritual Codfeast, or New Year Cod.

This one is for the besindige, the "cool-minded" people, who realise that after a week of feasting on roasted pork and crackling, goose and sausages galore - such as medister-polse, rullepolse, salami and blood- pudding - there is only one thing for it: a little in the way of Catholic moderation.

Strangely, I have failed to find any mention of Codfeast in the more esoteric volumes on fish by the likes of Alan Davidson and Jane Grigson, nor can I find any recipe for the fiskesennep, or fish mustard, that is central to the sauce. And yet, if you mention Codfeast to Danes, they will ramble off on a discourse about poached codling and floury potatoes swimming in butter, and the elusive mustard liquor in which the two are drowned.

At the best of times, boiled cod and boiled potatoes would sound like 18th-century penitential fare; post-Christmas it has the ring of the Christmas tree stripped of its baubles, which is misleading. It certainly reflects the austerity of a freezing cold country, but there is a lusciousness about the assembly that defies its make-up. And it is exactly what you feel like on the seventh day of Christmas.

In essence, it is a deconstructed fish pie. The sauce is plentiful: there is the mash made of potatoes and the tender flakes of cod and, in the fashion of gazpacho, there are a host of attendant "bits" for the diner to dress up the fish - finely chopped egg, chopped parsley, freshly grated horseradish and capers, and a squeeze of lemon. I have mixed feelings about this elaborate parade of garnishes. It actually works if you play with one at a time; if you go the whole hog, it ends up looking like an English interpretation of a curry.

There is a certain bravado involved. Schnapps and mustard has the same ring for the Danish male as beer and vindaloo for the British: an additional bowl of mustard, burning in the English tradition, is placed on the table. The men also get to eat the eyes of the cod and the famously tender cheeks - the bigger the cod, the bigger the cheek.

The mustard is all important, and it was this that eluded me: I came across just one mail-order supplier. In Denmark, it is sold in dry form, a blend of coarse-ground black and yellow mustard seeds which, when water is added, swell and gradually develop an intensely nasal aroma and bitterness. The solution, I find, is to break up an equal mix of black and yellow seeds in an electric grinder and to fortify it with a spoon of English mustard powder.

The flavour goes very well with the cod which, poached whole, is much stronger than the average fillet, and it has some of the character that emerges when you salt cod. I would make a point of doing extra, since it makes delicious fishcakes or pie the next day. I'm sure the cool-minded people of Denmark had that in mind.

Codfeast, serves 6

The codling needs to be arranged with your fishmonger. According to mine, it is easier to obtain two small fish about 212 lb in weight rather than a large 5lb one, as these tend to have the head removed at sea, and it's got to be the full, head-on creature (with gills removed). So you really need to find out what he can procure for you.

Fiskesennep:

112 tbsp yellow mustard seeds

112 tbsp black mustard seeds

1 tsp English mustard powder

Poaching Liquor:

1.75L/ 3 pints water

570 ml/1 pint white wine

100 ml/ 4fl oz white wine vinegar

11/2 tbsp sea salt

2 large carrots, trimmed and sliced

2 sticks celery, sliced

1 leek, trimmed and sliced

2 cloves

6 peppercorns

1 star anise

2 bay leaves, 2 parsley stalks, 3 sprigs thyme

Fish:

2 x 1.125kg/ 21/2 lb cod, or 1x2.3kg/ 5lb

Potatoes:

1.8kg/4lb maincrop potatoes

25g/1oz unsalted butter

Sauce:

50g/2oz unsalted butter

40g/13/4 oz plain flour

275ml/1/2 pint double cream

Garnish:

8 eggs, horseradish root, chopped flat-leaf parsley, lemon wedges, capers

Coarsely grind the yellow and black mustard seeds in an electric grinder. Add a few tablespoons of water to them (the amount it will absorb will differ, so add a little more as required). It can stand for up to a couple of hours. You probably won't need the full quantity; it should be added to taste.

To prepare the garnishes, boil the eggs for 10 minutes, then cool in cold water. Shell them and separate the yolk from the white; finely chop the yolk and half the whites (discard remainder), and place separately in bowls. Grate the horseradish close to the time of serving, since it discolours; you may be able to do this with an attachment on your food processor, but it may then need chopping more finely with a knife.

You can either cook the cod in a fish kettle, or what I do is to use a tea towel as a sling for the fish and cook it in a long casserole. Combine all the ingredients for the poaching liquor in whichever vessel, and bring to a simmer. Cover and cook for 20 minutes. Bring a pan of salted water to the boil for the potatoes.

Place the fish in the steamer or the casserole, bring the liquor to the boil, cover and cook for five minutes. Take off the heat and leave for 20 minutes. If you are cooking a large cod then you may need to simmer it for 10 minutes. Put the potatoes on to boil, so they are ready at the same time as the cod. Drain them. And add the butter and salt to the saucepan.

To make the sauce, melt the 50g/2oz butter in a medium saucepan and add the flour. Cook the roux for a minute or two, then gradually whisk in 900ml/11/2 pints of the poaching liquor. Add the cream and simmer for five minutes. Add two tablespoons of the mustard seed mix, blend the powder with a little of the sauce and add this, too. Adjust salt and add more of the wet mustard mixture if you feel it needs it. Serve the sauce separately at the table with the garnishes