Nigel Slater's Boxing Day turkey sandwich

There is one plate of food I look forward to more than any other – more even than Christmas lunch and certainly more than any restaurant reservation. It is that glorious Christmas treat: the Boxing Day sandwich.

I know, it's just leftovers held between two slices of bread. But what leftovers! Slices of turkey or goose, cut thin and generously salted; crisp salad leaves; some mayonnaise and soft, flour-dusted bread. To my mind there is no better sandwich than the one I make on Boxing Day with the bits left over from the day before.

Good as it is, my favourite sandwich in the world can only get better with a few carefully chosen bells and whistles: a thin layer of turkey dripping in the bread; a few rashers of crisp bacon hot from the grill (a must); a trickle of cranberry sauce; a slice of stuffing from the bird and – please, please – a few wisps of mahogany-coloured skin from the bird's breast.

There must, surely, be pickles. A tangle of shredded red cabbage; a spoonful of apple, onion or mango chutney; or an onion or two on the side. This may seem like the moment to test out the homemade chutney you unwrapped yesterday with such a grateful smile, but I wouldn't chance it. This once-a-year wonder is too precious to cock up. I'll experiment with cheese and someone's homemade date-and-rhubarb chutney later.

The bread might be better toasted, considering the day or two it has been waiting for its 15 minutes of glory, and somehow I doubt I'll be baking on Boxing Day. I don't think the toast should be too crisp for this – you want some softness in there, so a careful eye on the toaster is needed. I generally find a sourdough loaf a better bet over the holidays, as it seems to keep fresher, but you could always freeze a loaf especially for the purpose.

At this time of the year there are more people around than chairs on which to seat them. This is the point at which I make myself scarce, hunting out a quiet corner in which to sink my teeth into the best snack of the year. It is during this sandwich, invariably eaten with a glass of champagne, that I find a moment to take stock.

If ever there was an appropriate point at which to quietly digest the high points of the year, this is it: the roast home-reared pork and heaven-sent apple crumble at the Talbot Hotel in Knightwick, Worcestershire; Rowley Leigh's heavenly pike boudin at London's Le Café Anglais; St John's outrageously generous Eccles cakes scoffed warm from the oven with Hurdlebrook's unpasteurised cream. A bowl of fish soup in Helsinki's market; a vacuum flask of sprout- and-potato soup eaten while sitting on a snowy hillside as the sun went down over the Kent countryside; and the endless and exquisite dinner I ate at a tiny 10-seat restaurant in Kyoto. This is the plate of food with which I will quietly celebrate the passing year.

Of course it is a sandwich bolstered by soup – and this year a particularly frugal number made with left-over vegetables. It looks like soup but tastes like bubble and squeak. Leftovers have never tasted so good.

BUBBLE-AND-SQUEAK SOUP

I sometimes eat this with a little stuffing stirred in at the end. The recipe works best with lightly roasted potatoes. Bits from the roasting tin will increase the depth of flavour. A good homemade stock is a necessity here.

Serves 4-6

onion 1 medium, peeled and sliced
dripping or butter 2 tbsp
cooked potatoes and parsnips (boiled or, preferably, roast) 750g
thyme leaves 1 tsp, chopped
stock (turkey or chicken) 1.5 litres
lightly cooked greens (eg cabbage) 350g
single cream 150g
a fine grating of nutmeg

DIRECTIONS

Melt the dripping or butter in a large, deep saucepan and add the onion. Let it cook for 15 minutes or so, with a regular stir.

Chop the potatoes and parsnips into small pieces and then add them to the onions with the thyme. As soon as the potatoes are warm, pour in the stock and bring to the boil. Season, lower the heat to an enthusiastic simmer and leave, partially covered with a lid, for 25 minutes or so.

Chop the cooked greens and stir them into the soup. Continue to simmer for 15 minutes. Ladle two-thirds of the soup into a blender and/or food processor and blitz until smooth. Return to the pan and add the cream and a grating of nutmeg. Bring to the boil, stir, and pour into warm bowls.

THE BOXING DAY SANDWICH

It is worth mentioning a few points if the sandwich is to be memorable and worthy of its accompanying glass of champagne.

The meat should be sliced thinly. Thick chunks of cold meat are far from appealing.

You can never be too generous with the salt when serving cold meats and poultry.

Bacon – crisp, streaky and smoked – is pretty much essential.

Cranberry sauce, redcurrant jelly, chutney and slices of cold stuffing all have their place, as do crisp salad leaves.

The mayonnaise is particularly good when seasoned with any of the following: capers, chopped gherkins, tarragon, lemon zest, lemon juice, dill, chilli sauce, paprika, wasabi paste, grated fresh horseradish, crème fraîche and chives, or seeded mustard.

If the bread isn't as fresh it might be, then it is best lightly toasted.

Generosity is essential, but you will need to pick it up without it tipping out its cargo.

About 150g of meat per person is more than adequate… but really, who's counting?

If you aren't having the soup above, then sautéed potatoes will work nicely with your sandwich. The council of perfection would be to have them sizzling in duck or goose fat. On this day it is worth the expense.

Email Nigel at nigel.slater@observer.co.uk or visit guardian.co.uk/profile/nigelslater for all his recipes in one place

Thanks to guardian.co.uk who have provided this article. View the original here.