Head chef, The Connaught
A jambon beurre on a crispy baguette, ideally eaten in France because of the quality of the flour and water in the bread. I spread it with a salted butter from Bordier of Normandy, incorporating my signature espelette pepper, add gruyère cheese aged 18 months and iberico ham from Bellota-Bellota in Paris. It's cooked in stock and therefore particularly mild.
Chef and owner, Theo Randall
It has to be Poilâne bread with smoked salmon and capers, drizzled with olive oil. The Poilâne has a lovely chewy texture and the sourness pairs with the salty smoked salmon. The vinegary capers are a perfect addition as they also cut through the saltiness. I look for salmon with not too many pale white veins, which can be too fatty. Ideally, I would choose wild salmon, but that's a bit decadent for everyday. This is a lunchtime snack I like to eat while relaxing and reading the paper. It is healthy but incredibly tasty, which is why the ingredients are always in the fridge.
Head chef, Le Café Anglais
I don't think you can beat three not-too-crisp slices of streaky bacon between two slices of well-buttered industrial white bread. Sandwiches should be simple: cheese and pickle, egg mayonnaise and watercress, plain smoked salmon in brown bread with coarsely milled black pepper and a squeeze of lemon. The more complicated and ingenious they are, the more they lose their point.
Head chef, The Ledbury
It has to be fish fingers on cheap squidgy white bread with iceberg lettuce, ketchup and mayonnaise. Perfect – the ultimate comfort food on the rare occasion I get to eat a sandwich after a long service or on a day off.
Sandwich developer at M&S
I eat sandwiches all day long for work – extraordinarily, our prawn mayo has remained the best-seller since its launch 30 years ago – so I don't make that many for myself during the week. When I do, it has to be on a freshly baked baguette with proper salted butter – that's the most important part. I fill it with Parma ham, vine-ripened tomatoes and fresh basil leaves, or a steak cooked rare with caramelised onions and wholegrain mustard.
Chef and owner, Bocca di Lupo
I often recreate an early morning bite we used to delight in at Moro. We'd buy sandwiches from the caff opposite made with cheap pre-sliced brown bread, iceberg lettuce, back bacon with the fat crispy but the eye of the meat not overdone and eggs fried sunny side down with a runny yolk. Then we'd open them up and slather on lashings of Moro's fiery home-made harissa. You have no idea how potent a hangover cure this can be for breakfast.
Head chef, Umu
I like a crispy baguette with tuna sashimi, homemade wasabi dressing, mustard leaves and cucumber. I chop the raw tuna and mix with pine nuts and chives. Then I dress it with a mix of wasabi, mayonnaise, soy sauce, shiso leaf and lime juice. In Japan I used to have just steamed rice for lunch, and only started making this sandwich in London when my fisherman brought in some extra tuna for me to try. But now sandwiches are part of the culture in Japan.
Head chef, Koffman's
About once every two weeks I'll make a sandwich for myself and my partner Claire from a very good quality baguette. I don't put butter on the bread, but fill with a skirt steak pan-fried rare, a few fried onions and some Dijon mustard.
Head chef, The Spotted Pig, New York
I love roasted pork on an English country loaf that is crunchy outside but warm and soft inside, with crispy crackling, sage and onion stuffing baked in the oven and Maldon salt. It reminds me of growing up in Birmingham, and I feel very comfortable whenever I'm eating it.
Food developer, Gail's Bakery
My favourite is turkey from a freshly roasted bird with red slaw I make myself. I have access to all kinds of good bread, but prefer a sour cherry sourdough that is 50 per cent wholemeal. The coleslaw contains red cabbage, thinly sliced spring onions, sultanas, lemon juice and mayo. I spread the bread with English unsalted butter, flavoured with English mustard and a few flakes of Maldon salt. I'm suspicious of sandwiches that contain more than three ingredients.
Executive Sous Chef, Hakkasan, Hanway Place
My favourite is the Old Hong Kong Café fried spam sandwich. It was the first time I tried Western food as a child and the taste of butter and spam was heavenly. You take two slices of thick soft white bread, dip it in milk and then in beaten egg. Fry gently in a pan until the egg has cooked, then drain the excess fat on kitchen paper. In a clean pan, fry the spam, cut 5mm thick, until brown and place between the slices of bread. Season with black pepper and a dab of mustard. Melt a knob of unsalted butter in a clean pan, then fry the sandwich on both sides until crisp and golden brown. For me, this sandwich really represents Hong Kong in the 70s. The island was colonised by the English, French and Portuguese and the elements of the sandwich represent the best from each cuisine.
Head chef, Restaurant Nathan Outlaw
I like good bloomer or granary bread, preferably home-made and cut into doorsteps, spread generously with Cornish slightly salted butter, a few good slices of Davidstow "Crackler" cheese and a dollop of Branston pickle. Ideally, eaten with a couple of homemade pickled onions that really bite.
Head chef, The Pig, New Forest
A bacon sandwich on bread that has to be soft so it soaks up all the juices from the bacon as it cools. Mighty White was my original choice, but as I got older my taste leaned towards oaty granary bread. I spread it with Hellman's, the only mayo I eat apart from my own homemade, mixed with Colman's English mustard – a match made in heaven. The bacon has to be Smoked Hampshire middle-cut from Bartletts, a master pig butcher in New Milton. It incorporates both back and streaky, cooked nice and crispy so you get the best of both worlds.
Chef and owner, Zucca
Toasted ciabatta with buffalo mozzarella, tomato and rocket. The warmth of the toasted bread gently melts the cheese, the sweetness of the tomato is a perfect foil and the rocket adds a touch of heat. I make the ciabatta myself, toast it and drizzle all over with a really good olive oil. The mozzarella comes in fresh from Italy twice a week from a small farmer just outside Naples. When in season San Marzano tomatoes are best... the flavour is unsurpassed and they have a lovely dense texture. If you can get your hands on it, the rocket from Liguria is amazing – so strong and crisp.
*To celebrate National Sandwich Week Independent.co.uk is making an image gallery of readers' sandwiches. Email your pictures to email@example.com for publication, with your name, location and the contents of your sandwich.