It may not be much of a looker, but celeriac is one of the most versatile of all winter veg. In fact, it’s my favorite root of all time.

I’m shining the spotlight on another vegetable that is perhaps even more unprepossessing, with knobbly, knotted looks that only a mother could love – or a cook who has unearthed its inner beauty. I’m going to go out on a limb here and say that celeriac might just be my favourite root of all time. It’s nothing less than a winter wonder.

For starters, the versatility of this vegetable is incredible. Look at this week’s recipes: a crunchy, vibrant raw salad, a tummy-warming gratin and – wait for it – an unforgettable ice-cream! And I didn’t have room for a soup, a mash, a slaw or a curry… Not even the potato has such range. Next among celeriac’s under-appreciated star qualities is its fine texture – delicately crisp but still yielding when raw, tender as butter when boiled or baked, wonderfully velvety but never gluey when mashed or pureed.

But what it all comes down to most is the flavour. Celeriac is closely related to celery, a vegetable that’s vital for giving body and depth to everything from stocks and soups to salads. Both contain compounds known as phthalides (great Scrabble word) that have been shown to have an almost magical ability to enhance the flavours of other ingredients, as well as terpenes, which contribute citrussy, resinous notes. But where celery’s flavour is assertive, celeriac’s is mellow. Celery has a slightly harsh edge, but celeriac is more complex and sophisticated: nutty and earthy, yet highly aromatic. Among its many notes, it even has a touch of the oyster about it – and that’s pretty sexy. Sexy, but comforting. Whether used alone or in combination with other ingredients, celeriac is a warm, voluptuous, creamy hug of a vegetable.

A celeriac root (actually, technically it’s a corm, or swollen, semi-buried stem) is rounded and relatively smooth at the top end, but the base is a tangle of searching, knotted tendrils that hold on to lots of earth. When preparing it, don’t muck about with a peeler, but just set to with a large, sharp knife and cut away all the rooty bits and the skin. You’ll create a fair bit of debris – allow for losing 10-20% of its original weight by the time it’s prepared – but it’s by far the easiest way. Clean your trimmings and the peel – and the stalks and leaves, if they were still attached – because they will all add wonderful flavour to any stock. The white flesh will brown quickly when exposed to air, so add it almost straight away to water, cream, milk or a dressing.

I think the great appeal of this root lies in its curiously eager-to-please character. It’s mild enough to serve raw, yet has enough gentle pungency to hold its own in a show-stopper dish next to strong-flavoured ingredients. Celeriac is beefy enough for beef, for instance – or venison or game, for that matter – but it’s also delicate enough for chicken. In fact, a buttery, well-seasoned puree of the root is a wonderful accompaniment to any of these meats.

This vegetable loves to be in the company of other winter roots such as carrots and parsnips. It pairs especially beautifully with potato and I often combine these two in a mash or soup. You can go 50/50, but even a small amount of celeriac will intriguingly transform your mash. I cook the celeriac in milk, then blitz it and mash the resulting milky puree into the cooked spuds with a good knob of butter. Celeriac gratins – either all-celeriac or a combination of roots – are a staple in my house when the weather is cold, and I like to experiment with adding different flavours, spiking them with chilli, garlic, herbs, even lemon zest.

Don’t forget celeriac with fish, either, which can be a particularly felicitous combination. A fillet of bream or bass, fried until crisp-skinned and served with a little bacon and a creamy celeriac puree, or the mixed mash described above, is quite divine. As is a luxurious, velvet-smooth leek and celeriac soup with a poached oyster or two sitting on top. Alternatively, simply roast some cubes of celeriac with a few other roots, lots of bay leaves, thyme and garlic, then place a whole or filleted fish on top and return to the oven to complete cooking.

But some of my favourite ways to eat celeriac are completely vegetarian dishes, particularly salads. Raw and julienned (cut into fine matchsticks), it is a masterful ingredient on a platter. I often mingle it with puy lentils, flat-leaf parsley and juice-soaked raisins. It’s fantastic with fennel (their seasons overlap in October and November), as well as with fruits such as apple and orange, which can make a winter savoury salad so wonderfully aromatic and refreshing.

And then, of course, there’s the deservedly classic celeriac remoulade – thin little strips of the raw root folded into a rich, mustardy mayonnaise. Give me a dollop of that with a few cold slices of my Christmas ham and a hunk of bread, and I’m a very, very happy man indeed.

Celeriac, chicory and orange salad with toasted cashews

I love raw celeriac in a salad. Its flavour, both earthy and sweet, balances piquant, sharp or bitter ingredients beautifully. Serves four.

75g cashew nuts
2 tbsp olive oil
½ tsp English mustard
2 tsp cider vinegar
Sea salt and freshly ground black pepper
250g celeriac
1 head chicory
1 large orange

Put the nuts in a dry frying pan, toss over a medium heat for a few minutes until lightly toasted, then set aside to cool.

Combine the olive oil, mustard and vinegar with some salt and pepper, and tip into a mixing bowl. Peel the celeriac and cut it into matchsticks. Toss the julienned root immediately in the dressing to stop it from browning. Trim the chicory and separate the leaves, then add to the celeriac in the bowl. Spread the dressed celeriac and chicory on a plate.

Cut a slice off the base of the orange and stand it on a board. Use a sharp knife to cut through the peel and pith of the orange, slicing it away completely, in sections. Working over the plate of celeriac so any juice that escapes will fall on to it, cut out the individual orange segments, letting them drop on to the salad as you go. Squeeze any juice out of the remaining orange membrane over the salad. Add some more salt and pepper to taste, scatter over the cashews and serve.

Celeriac ice-cream with walnut praline

This might sound a bit wacky, but it works. Serves eight.

For the ice-cream
300g celeriac, peeled and cubed
500ml whole milk
8 large egg yolks
150g caster sugar
300ml double cream

For the praline
150g granulated sugar
75g walnut halves, roughly broken up
½ tsp flaky sea salt

Put the celeriac and milk in a large pan, bring to a simmer and cook, stirring from time to time, for 20-30 minutes, until the celeriac is tender. Using either a stick blender or a jug blender, puree the celeriac with the milk until very smooth. Measure out 300ml of the puree for the ice-cream; any leftover puree will work very well in a soup.

Whisk together the egg yolks and sugar. Pour the hot celeriac puree over the egg mixture, whisking as you go, then pour this mixture into a clean saucepan. Place over a moderate heat and cook, stirring continuously, until thick enough to coat the back of a wooden spoon. Pour the mixture into a bowl, stir in the cream and put a piece of cling-film over the surface to stop a skin forming. Set aside to cool, then chill. When completely cold, churn in an ice-cream machine (you’ll need one with a 1.5-litre capacity for this amount of custard) until soft-set, then freeze until solid. Transfer to the fridge for 30 minutes or so before serving, to soften a little.

To make the praline, lightly oil a baking sheet (or line it with baking parchment or a nonstick baking mat). Put the sugar in a heavy-based saucepan with a light-coloured interior to make it easier to see the colour of the caramel.

Put the pan over a low heat and, stirring with a rubber spatula from time to time, wait until the sugar melts. Stop stirring now and let the sugar cook until it has turned a dark amber colour.

As soon as it reaches the right shade, remove from the heat, stir in the walnuts with a fork and immediately pour on to the prepared sheet. Sprinkle the salt over the top and leave to set. When set, chop or break into small pieces. Store in an airtight container until needed.

To serve, divide the ice-cream between eight small dishes or glasses and add a liberal scattering of walnut praline.

Potato, pear and celeriac gratin

The very talented Sophie Wright made a lovely version of this in my new Channel 4 show, Hugh’s Three Good Things. The addition of pears enhances the celeriac’s sweet, aromatic quality. Serve with something hearty, such as slow-cooked shoulder of lamb or pork. Serves six as aside dish.

1 knob butter
About 400g floury potatoes
About 400g celeriac
2 firm, medium pears (about 300g)
Salt and freshly ground black pepper
400ml double cream
100ml whole milk
1 clove garlic, peeled and halved
1 bay leaf
1 good grating nutmeg

Heat the oven to 170C/335F/gas mark 3. Rub a gratin dish with the butter.

Peel the potatoes and slice them thinly, either with a sharp knife or a mandoline. Cut the outer layer off the celeriac and slice this thinly, too. Peel, quarter and core the pears, and slice each quarter thinly lengthwise. Combine the vegetables and pear in a bowl, season and toss. Arrange the mixture in the gratin dish, pressing it as flat as possible so there are not too many gaps and air pockets.

Put the cream and milk in a saucepan with the garlic halves, the bay leaf, the nutmeg and plenty of salt and pepper, and heat until just below boiling. Pour over the veg in the dish (take the bay leaf out at this stage, but keep the garlic in).

Bake for an hour and a quarter to an hour and a half. The gratin is ready when the top is golden and bubbling, and a small, sharp knife easily pierces the vegetables all the way through. You may want to turn up the heat to 190-200C (gas mark 5 or 6) for five minutes at the end for a bit of extra bubbling crispness. Leave to rest and cool for five minutes or so before serving.

• River Cottage cookery courses and dining events are available as Christmas gifts – go to rivercottage.net for details.

Hugh Fearnley-Whittingstall’s celeriac, chicory and orange salad with toasted cashews: Earthy and sweet. Photograph: Colin Campbell for the Guardian.