A salad worth roasting for

Salads get a rough ride in January. They arrive at the table pale, cold and apologetic, as though someone has forgotten that it is nine degrees outside and we would all rather be eating a stew. But a winter salad is a different creature entirely. Roast the vegetables until their edges catch and their sugars deepen, add something salty and something crunchy, and pile it all onto leaves with a bit of bite, and suddenly you have a plate that feels generous rather than penitential.

This combination works because every element has a job. Earthy beetroot brings sweetness and depth. Feta cuts through that sweetness with salt and acidity. Toasted walnuts add crunch and a faint bitterness. Peppery leaves — rocket, watercress, land cress — stop the whole thing becoming too rich. It is quick once the oven has done its work, it looks impressive on a platter, and it sits happily alongside roast chicken, sausages or a baked potato.

Roasting beetroot so it actually tastes of something

Heat the oven to 200°C (180°C fan, gas mark 6). Buy raw beetroot if you can — about 500g for four people as a side — and choose medium ones, roughly the size of a small apple. Larger roots are woody in the middle and take far longer.

Leave the skins on. Scrub them well under running water, trim the tail, and leave a couple of centimetres of stalk at the top so the juices stay inside. Wrap each beetroot individually in foil with a splash of olive oil, a good pinch of flaky salt and, if you have it, a sprig of thyme or a bruised garlic clove. Sit them on a baking tray and roast for 45 to 70 minutes, depending on size.

• The test: a small knife should slide in with no resistance at all, right through the middle.
• If in doubt, give them longer. Underdone beetroot is firm and disappointing; overcooked beetroot is sweet and soft, which is no bad thing here.
• Cool slightly, then rub. Kitchen paper will lift the skins away easily while the roots are still warm. Wear an apron, and don't use your best tea towel.

Cut the peeled beetroot into wedges. If you are short on time and can only buy the vacuum-packed cooked sort, don't despair — tumble the wedges in oil and salt and roast them at 200°C for 15 minutes. Those caramelised edges make a real difference.

The supporting cast: leaves, feta and walnuts

Use 100–120g of leaves. A bag of rocket is fine, but a mix is better: watercress for heat, lamb's lettuce for softness, and a few leaves of red chicory or radicchio for a pleasant bitterness that echoes the walnuts. Wash them and dry them properly — a salad spinner or a clean tea towel. Wet leaves dilute the dressing and go limp within minutes.

For the cheese, buy a block of feta in brine rather than the pre-crumbled sort, which is dry and dusty. Break about 150g into rough, uneven chunks with your hands. Let it come to room temperature before serving so it tastes creamy rather than fridge-cold. A soft goat's cheese or a gentle blue would also work beautifully.

Toast 60g of walnut halves in a dry frying pan over a medium heat for three or four minutes, until they smell nutty and have darkened a shade. Keep them moving. Alternatively, scatter them on the tray beside the beetroot for the last eight minutes. Cool them, then break them up roughly.

The dressing that ties it together

Beetroot is sweet, so the dressing needs to be sharper than you might expect. Shake the following together in a jam jar:

• 1 tbsp cider vinegar, or sherry vinegar if you have it
• 1 tsp Dijon mustard
• 1 tsp runny honey or maple syrup
• 3 tbsp extra virgin olive oil
• Sea salt and plenty of black pepper

Taste it on a leaf. It should make you wince very slightly, then soften. If it tastes flat, add a few drops more vinegar; if it tastes harsh, a little more oil.

Here is the one trick worth remembering: toss the warm beetroot wedges in half the dressing as soon as they are cool enough to handle. Warm roots absorb dressing like a sponge, and the flavour travels right through them instead of sitting on the surface.

Building the salad and serving it

Spread the leaves over a wide platter or a shallow bowl. Spoon the dressed beetroot over them, letting some of the pink-stained juices run into the leaves. Scatter over the feta, then the walnuts. Spoon the remaining dressing over the cheese and leaves, and finish with a handful of chopped dill or flat-leaf parsley — dill is particularly good with beetroot.

Serve it straight away, while the beetroot is still faintly warm against the cool leaves. It is excellent next to roast chicken thighs, a plate of good sausages, or a jacket potato with too much butter. It also holds its own as part of a spread, alongside a wedge of quiche, some cold roast lamb, or a bowl of butterbeans dressed with olive oil and lemon.

Getting ahead and ringing the changes

Roast the beetroot up to three days in advance and keep it in a lidded container in the fridge. Toast the walnuts at the same time. Make the dressing in a jar, where it will keep for a week. That leaves five minutes of assembling on the day, which is exactly the sort of cooking that suits a cold evening.

Once you have the formula, it bends easily. Swap the feta for goat's cheese. Add orange segments in February when the citrus is at its best, or a scattering of pomegranate seeds. Toasted pumpkin seeds can stand in for the walnuts. Stir a handful of cooked puy lentils or pearl barley through the dressed beetroot and it becomes a main course in its own right. A spoonful of yoghurt mixed with a little creamed horseradish, dolloped over the top, is a fine addition to a roast dinner.

And do try adding a teaspoon of cumin or coriander seeds to the foil when the beetroot roasts. It is a small thing, but it turns a good salad into one people ask you about. That is the quiet pleasure of seasonal cooking: taking what the cold months give you, treating it with a little patience, and letting it taste of itself.