Why quick pickles earn their place in the fridge

There is a quiet pleasure in opening the fridge and finding a jar of something you made yourself, bright with vinegar and still properly crunchy. Proper pickling takes weeks and a cupboard full of equipment. A quick pickle — sometimes called a refrigerator pickle — is ready in an hour, needs nothing more exotic than vinegar, sugar and salt, and will happily sit in the door shelf for a month.

Cucumbers and onions are the classic pairing, and for good reason. Cucumber brings water and crunch, onion brings sweetness and bite, and the brine swaps one for the other: the onion softens, the cucumber sharpens, and the whole lot turns into the sort of thing that lifts a plain cheese sandwich into something you would pay good money for at a deli.

If you grow your own cucumbers, this is also the answer to that awkward week in August when four of them ripen at once and the salad drawer gives up.

What you need

Any cucumber works, though the long, thin-skinned ones sold as ridge or mini cucumbers hold their crunch best. One large cucumber or three or four small ones is about right.

• 1 cucumber, roughly 400g, sliced no thicker than a two-pound coin
• 1 medium red or white onion, sliced as thinly as you can manage
• 200ml white wine vinegar or cider vinegar — malt works but tastes distinctly British and rather assertive
• 100ml water
• 2 tbsp caster sugar, or 1½ tbsp runny honey
• 1 tsp fine sea salt
• Optional extras: 1 tsp mustard seeds, ½ tsp black peppercorns, a bay leaf, a pinch of chilli flakes, a few sprigs of dill

You will also want a clean 500ml jar with a lid, and ideally a mandoline or a very sharp knife. A jam funnel helps if you are clumsy with a ladle, which most of us are.

The method, step by step

Step one — salt the cucumber. Toss the sliced cucumber with a teaspoon of extra salt in a colander and leave it for twenty minutes. Water will bead and drip out. Rinse briefly, then pat dry with a tea towel. This is the single trick that keeps quick pickles crunchy rather than limp, so do not skip it if you can spare the time.

Step two — soften the onion. Slice the onion thinly, then rinse the slices under cold running water for a few seconds. This takes the harsh raw edge off without losing the flavour.

Step three — make the brine. Warm the vinegar, water, sugar and salt in a small saucepan over a low heat, stirring until the sugar and salt dissolve. You want it steaming, not boiling, and you should not need more than three or four minutes.

Step four — pack the jar. Layer the cucumber and onion into the jar, tucking any spices or herbs between the layers. Pour the warm brine over the top until everything is covered by at least a centimetre. Tap the jar on the worktop a couple of times to knock out air bubbles, then top up if needed.

Step five — wait. Leave the jar to cool on the worktop, then refrigerate. They are perfectly good after an hour, noticeably better after a day, and at their best somewhere between day two and day ten.

Variations worth trying

The basic ratio above is a template rather than a rule. Once you have made it once, you can adjust with confidence.

• Dill and garlic: add two crushed cloves and a generous handful of dill for something close to a deli-style pickle.
• Sweet and mustardy: push the sugar to 3 tbsp and add a tablespoon of yellow mustard seeds — excellent with cold meats.
• Hot and sharp: add a sliced red chilli and a teaspoon of black peppercorns, and cut the sugar back to 1 tbsp.
• Apple cider and fennel: swap in cider vinegar and add a teaspoon of fennel seeds for something that suits fish beautifully.

Growing your own in a small space

Neither crop asks for a garden. Cucumbers will happily climb a wigwam of canes in a 30cm pot or a growbag against a south-facing wall, and the smaller varieties bred for containers are far more productive than people expect. Water them consistently — irregular watering is what makes cucumbers bitter — and feed weekly once the flowers set.

Onions are even easier. A window box of spring onions sown from seed gives you a constant supply of something to slice into the brine, and pickling onions grown from sets will crop in a large pot on a balcony. If space is truly tight, a pot of chives on the sill does the job of the dill and the onion at once.

Storing and using them up

Keep the jar in the fridge with the vegetables fully submerged, and they will last three to four weeks. Vinegar is corrosive over long periods, so if your jar has a metal lid, lay a square of greaseproof paper underneath it to protect the lining.

Use them anywhere you would use a gherkin: piled into sandwiches, alongside a ploughman's, chopped through potato salad, on top of a burger, or spooned next to a curry to cut through the richness. The brine itself is worth keeping — a splash of it makes an instant salad dressing, and a spoonful stirred into mayonnaise turns it into something far more interesting.