Wondering what to do with a glut of onions or shallots? You’d only need to have a passable interest in cooking to have experienced a vegetable drawer so stocked, stacked and burgeoning with alliums that decisive action is required. Fortunately, both onions and shallots lend themselves incredibly well to preserving, in doing so saving them from the compost heap and turning them into a superb and versatile condiment. Here’s our favourites; our 5 IDEAL things to do with leftover onions and shallots.


Pickling is a diverse tool to have in your cooking arsenal, whether you’re quick pickling, going for a longer pickle, brining or sousing. Then, there’s all the flavours you can add to the pickle, usually in the form of dried spices and their seeds, but also determined by your choice of vinegar, and the addition of fresh herbs and supplementary vegetables. It’s that diversity which makes this such a great preserving method, and onions and shallots are some of the greatest beneficiaries of the age-old technique.

Perennially popular, particularly on home turf in Britain, is to pickle onions whole; peeled, pickling (sometimes called pearl or baby) onions or round shallots are salted overnight in a colander, ensuring crunch in the final product. A mix of malt vinegar and sugar (or honey) at a ratio of 3:1, with added coriander and mustard seeds, is then warmed until thoroughly dissolved, and poured over the onions, which have been packed in a sterilised jar. The finished pickled onions are ready in around a month. Once they’ve been opened, keep them in the fridge. These are absolutely delicious with cheese, particularly as part of a Ploughman’s lunch, or with fish and chips.

Alternatively, you can quick pickle sliced onions or shallots in a Vietnamese style. Here, you should simply combined vinegar and sugar in a bowl (the ratio is up to your personal preference of sharp against sweet) and then add your sliced onions and perhaps some thinly sliced chilli. Mix thoroughly and let sit for around 15 minutes. These are enjoyed straight away; perfect in a chicken salad or as part of the intricate flavour and texture building of a fine banh mi sandwich.


Lacto fermenting is a complex and diverse term, but here we’re talking about preserving onions in a salt brine solution, in an anaerobic environment, in order to add crispness to their texture, a delicate, delicious sour flavour, and to unleash the onion’s probiotic potential in the process. 

Simply pack sliced onions or shallots into a sterilised Kilner jar, add water to cover and then weigh the jar. Calculate 2% of that weight, and convert that amount into salt. Say your Kilner jar, water and onions weighed 1000g, then that’s 20g of salt.

Mix everything together in a scrupulously clean bowl, then add back to the Kilner jar. Fill a ziplock bag with water, making sure there’s no air inside, and use it to weigh down the brine and onion mix, to keep the vegetables submerged, and close the lid. With the hard work done, you simply leave the fermentation to occur, opening the lid each day and removing the weight to ‘burp’ the mixture. After roughly a week, you’ll have a complex and versatile condiment which is superb on burgers or in hot dogs, as well as added to salads. 


Crispy shallots are a hugely popular addition to a vast array of curries, salads and dips in South East Asia, though they’re so moreish we could well eat them on their own as a snack, or even a meal. Ok, maybe not a meal, that would be weird. 

Anyway, slice your shallots against the grain thinly, though not quite gossamer style, and dry them thoroughly on paper towel. Starting in cold oil, add your shallots and bring the pan up to medium heat. Stir regularly in a clockwise motion (perhaps it’s an old wive’s tale, or maybe it does indeed elimate the pockets of colder and hotter oil, but it works for us) noticing the delicate change in colour. 

Once the shallots are golden, but a shade down from what you’re hoping the finished product to look like, remove them from the oil with a slotted spoon onto more kitchen towel. Be warned that this is a delicate business and the residual heat will take the shallots through to the perfect colour once they’re out of the oil; take your eye off the ball and in a blink, they’ll be overdone and bitter. Store the crispy shallots in an airtight container in a cool, dark place, preferably with a silica gel bag added to soak up any excess moisture, for up to five days.

These are amazing as a garnish for Thai coconut based curries, as a topping for traditional Danish hotdogs or baked potato, and added to various Vietnamese soups, salads and dumplings. 


No cheese board would be complete without it, right? Needing little in the way of introduction, an onion chutney is indispensable alongside goat’s cheese particularly, as well as with cold cuts of meat or even on a pizza. 

Simply slice or dice (depending on the texture you’re looking for) a good couple of kilos of red onions thinly and fry gently, with a bayleaf added, for at least half an hour, but preferably even longer, until sticky and caramelised but not burnt.

Add 500 grams of muscovado sugar, and 250ml of balsamic and 500ml of red wine vinegar, as well as a generous pinch of salt, and simmer on a low heat, letting it bubble gently for an hour or so, until thickened and jammy. If in doubt, run a spoon through the middle of the pan; a good few seconds should pass before the mixture meets again.

Once you’re satisfied with the consistency, spoon into sterilised jars and allow to cool. This guy will keep in the fridge pretty much indefinitely.


Use up a glut of white onions in style by making a big batch of this French bistro classic, and keeping what you resist eating the first time round in the freezer. Whilst we’d love to sit around talking about onions, we’ll let the don Raymond Blanc play us out on this one. Check out his recipe for a classic French onion soup over here. And with that, happy cooking!