The Basics of Pickling and Fermenting
…and the recipe for Jerusalem mushroom mixed grill.
You know how Nigella goes to the fridge at night and takes out a piece of chocolate cake to crush a craving or sudden hunger? My version couldn’t be more different. If I am kept awake, needing to fill a void, there is only one answer: a pickle.
Well, not quite; it’s actually a bit embarrassing. I have mini-sandwiches made of two crispy crackers, spread with mayonnaise (Thomy is my first choice), topped with cheese (cheddar or Lancashire) and a pickle. Whichever pickle or ferment I happen to have will work, but ideally, it should have a bit of sweetness. The key is in the balance of textures, creamy cheese and just the right amount of knockout pickle to cut through everything.
Luckily, I don’t need to go far for my pickle inspiration. My restaurant, ROVI, is only 20 minutes away from home and it’s got shelves crammed with large jars that are themselves crammed full of things that are pickled, brined or fermented.
ROVI is built around a big wood-fired grill where the majority of the dishes on the menu start their lives: large heads of celeriac, bulbous onions, a whole tranche of brill, fluffy pittas. The pickles and ferments aren’t there by chance. They are there to sit beside the smoky-fatty-spicy things that come off the grill – give them contrast and cut through their richness.
Today’s recipe – my Jerusalem mushroom mixed grill – is a childhood classic for me… and now a ROVI classic too. Traditionally, it’s bits-and-pieces of chicken – hearts, livers, spleens– peppered with baharat-like spice mix and cooked quickly on the plancha with lots of onion. It’s served with warm pita. For me, pickles (traditionally cucumber, turnip, carrot or cauliflower) are an essential condiment. They actually make the dish, since they break right through the uniform mound of meat and give it extra character.
At ROVI, we swapped meat with mushrooms: oyster mushrooms, king oyster, and shiitake. They mimic the meaty textures, spiced and grilled just the same.
The pickle selection at ROVI is different (cucumber, daikon and red onion) and we really try to push the boundaries beyond the old grillhouses. We pickle everything: gooseberries, onions, lemons; shiso leaves, kohlrabi and cabbage. Every time I pass, I lift a jar, crack it open, and take a sniff (not sure what the guests on nearby tables are thinking...). It’s like a little science experiment, each one at a slightly different stage of its life.
Andy (our Head Chef at ROVI) could easily catch me mid-sniff of a green tomato pickle, tangy and super-sharp. It’s been a staple since day one, a way to use up tomatoes that refuse to ripen in time. It started as a necessity but turned into something we can’t do without.
ROVI has always been about stripping things back, letting humble ingredients shine. And preserving is central to that. Andy has a knack for making it sound simple: “Taking something good and in season and making it last”.
How to pickle (and not get in a pickle)
Some of the preserving at ROVI is much more involved than Andy lets on, but honestly, pickling can be wonderfully simple. Clean jars, a basic brine (vinegar, water, salt, sugar), and you’re halfway there.
The vinegar you choose matters, though – red wine for something robust, apple cider for a softer note, white wine for something delicate. And then, it’s up to you: add spices, garlic, herbs, and maybe a few chillies. Slice your vegetables evenly, tuck them into the jar, pour over your brine, and seal tightly. Now comes the hard part: waiting.
Even after just a few hours, you’ll taste that fresh, crisp shift – that quick pickle with a satisfying crunch. But leave it longer, and the flavours deepen, become richer, more complex.
A little tip from me: if you want that extra crunch, try salting your vegetables before pickling. Rinse and pat dry before you pack them into the jars. It makes all the difference.
The most common pickle in my house (it’s actually a ferment, that then gets an extra pickle kick by adding vinegar), and my first suggestion for pickle debutants, tends to be shatta. It’s a Palestinian chilli sauce, popular throughout the region, that goes with everything – eggs, fish, meat, veggies... I always keep a jar in the fridge. Sometimes, the oil firms up and separates, but just a quick stir is all it takes to bring everything back together.
Red chilli shatta
Makes 1 small jar | Prep time 10 minutes | Pickle time 3-6 days
Ingredients
200g red chillies, roughly chopped seeds and all
2 tsp apple cider vinegar
3 tbsp olive oil
Flaked sea salt
Method
Place the chilli and 20g of salt in a food processor and pulse until coarsely blitzed. Place in a sterilised jar, cover loosely with reusable wrap or cling film to allow the air to circulate and set aside in a cool place at room temperature for 3-6 days until fermented to your liking. Mix in your vinegar then seal with the oil and keep refrigerated.
Pick ‘n’ mix pickle plate
While shatta is my go-to, my real snack addiction is those jars of sliced vegetables – cucumbers, radishes, onions, cauliflower. All lined up in my fridge, ready for snacking whenever I feel that pickle itch.
This little selection is the perfect companion to my Jerusalem mixed grill (more on that later), but don’t feel like you’ve got to make all of them. One variety is also great. Make a big batch, and you’ve got pickles to last you a while.
How to ferment
While pickling is quick and sharp, fermenting takes its time—and rewards your patience. It’s about the magical, bubbling relationship between bacteria and their surroundings. With just salt, natural bacteria work their magic, transforming whichever ingredients you choose into something deeper, richer, and more layered.
You’ll see it happening: tiny bubbles rising, the telltale sign of life. It’s a tactile, sensory process that’s as much about touch and smell as it is about sight (if it’s gone wrong, you’ll know – it’ll mould).
If you want to start fermenting at home, I can’t recommend Sandor Katz’s The Art of Fermentation enough (or this quick intro if you don’t want to add anything else to your bookshelf). It’s my fermentation bible — the first guide I found that made the process feel both approachable and meditative. But if you just want to dip your toes in, I asked my test kitchen for a few simple ways to get going:
Choose your veg. Go for something with plenty of water—cabbage, carrots, radishes—they’re beginner-friendly and work a treat.
Add salt. The magic ratio is 2% salt to veg weight. This keeps the bad stuff out, letting the good bacteria grow.
Massage and pack. Give your veg a proper rubdown with the salt until it’s juicy enough to cover itself. Pack it snugly into a clean jar, making sure everything stays beneath its brine.
Seal it up. Fermentation happens in a no-oxygen zone. Use a weight, a blue cloth, or even a big cabbage leaf, to keep your veg tucked safely under the liquid.
Wait and taste. Leave your jar at room temperature for a few days or weeks. Crack it open occasionally to let out the gas (some call it burping…). And while you’re at it, give it a sniff and a taste to check how it’s coming along.
Sauerkraut
A jar of sauerkraut is the perfect place to start. I’ll toss it in a toasted sandwich or, as we've done at both ROVI and on our new menu in Geneva, top it on some Hungarian langos bread, with a little sour cream.
Ingredients
1.8kg white cabbage
2 tsp caraway seeds
1 fresh bay leaf
36g flaked sea salt
Method
Slice the cabbage thinly and toss it with salt and spices. Let it sit for about 4 hours to macerate. Once it's ready, pack it into clean jars, leaving about a 1 cm gap at the top. Make sure the cabbage stays fully submerged in the liquid — you can use a weight or a piece of parchment paper to keep it down. Then, place the jars in a cool, dark spot and let them ferment for 2 weeks.
Some of the best discoveries happen when things go slightly off-script. ROVI’s sour onions, for example, began life as a simple pickle. With not enough pickling liquid, and left to sit a little too long, they began fermenting—something meant to be sweet and piquant turned sour and funky…and the perfect topping for our mushroom and brown rice congee (to which they still sit proudly on top).
Neil, our Executive Chef and another of my fermentation agony aunts, has his own go-to guide: Sam Cooper’s The Fermentation Kitchen. It’s a more stripped-back take, focused on turning what’s already around you—surplus vegetables, wild finds—into something else. I watched him press apples for cider in a sunlit orchard, another YouTube rabbit hole I fell into recently, and couldn’t help but feel the pull of it all: simple ingredients, a little effort, and a sense of satisfaction you can’t quite explain. If you’re curious, his Substack is full of inspiration…the man has a knack for making even the most ambitious projects seem entirely possible.
As for tools, you don’t need much. A few jars will do the trick for most projects, and beyond that, you can build as you go. But if you’re looking for a more comprehensive list, it’s worth consulting everyone’s trusted friend (Serious Eats).
BTW, if you’re in London, now’s the perfect time to start thinking about all things fermenting—@kenjcooks, the ferment king himself, is at ROVI for a collab until tomorrow (Sunday 16th January), bringing his expertise and a few surprises to the bar. Plus, by popular demand, we’ll be keeping some of his best ferments on hand, peppering them across our menu until they’re all gone…
Jerusalem mushroom mixed grill
Back to my mixed grill. In Jerusalem, the mixed grills tend to be offal—funky, gamey, rich–spiced and charred. It’s a bold mix of flavours and textures, with a mound of pita on the side.
At ROVI, we offer a mixed grill of only mushrooms: shiitake, oyster, and king oyster. Though we’ve adapted it, much remains the same: that rich, smoky profile, with earthy mushrooms and the acidity of the pickles. Our mushrooms come from Stein and Ella at Brambletye fruit farm in East Sussex, whose mushrooms bring such intensity and texture that you’d think they were born for grilling.
At ROVI, the oil gets a proper two-day infusion, but at home, I’m a bit more laid-back. I stick to fewer types of mushrooms and use the pickles already in my fridge (usually cucumber, red onion and daikon, as on my pickle plate). Or, if you're short on time, shop-bought ones are absolutely fine.
The real trick, though, once you have all your components ready, is to stuff everything generously into that warm pita. You’ll know it’s right when you’ve got tahini running down your hands. It’s gloriously messy…the best dishes always are.
Prep 15 mins
Cooling and infusing 30 mins
Cook 40 minutes