Buckingham Palace

Goya (34 Lupus Street, 020-7976 5309, goyarestaurant.co.uk) is about 15 minutes' walk from the palace but its fantastic, authentic tapas (from around £5, mains from £14) and atmosphere is well worth the stroll. If you fancy something heartier, L'Arco (79 Buckingham Palace Road, 020-7834 1151, larco.co.uk), a family-run Italian restaurant, is much closer and has a delicious, big-hearted menu with lots of choice outside the pizza and pasta remit (starters from around £6, pizza and pasta £8, meat and fish £12). Hidden at number 14 on quiet, nearby Eccleston Street is Jenny Lo's Teahouse (020-7259 0399, jennylo.co.uk). Its colourfully painted windows obscure the busy cafe within, but venture inside for the fresh, mainly Chinese menu (mains around £8) with some nice surprises such as Sichuan aubergines and Vietnamese cold noodles.

St Paul's

If you're visiting St Paul's during the week, expect to queue for food at lunchtime – suited city workers throng every cafe and restaurant from 1pm-2pm. But if you eat a little earlier or later, there are plenty of options. Tsuru Sushi (15 Queen Street, 020-7248 1525, tsuru-sushi.co.uk) is a great spot for varied Japanese food – the sushi is practically flapping it's so fresh, and the selection of hot bento boxes is great. Its most popular dish is a chicken katsu sandwich, which is almost worth travelling across town for. There's a great selection of sakés, too. Exmouth Market (exmouth-market.com) is about 30 minutes away on foot. Here, as well as popular bars and restaurants such as the ever-brilliant Moro (020-7833 8336, moro.co.uk) there is a lunchtime food market from noon-3pm Monday-Friday where you can eat anything from Ghanaian street food to crepes, Bangladeshi lunchboxes and salt-beef sandwiches from about £5.

Tate Modern

If the sandwiches in the Tate Modern's cafes leave you feeling flat, Elliot's Cafe (12 Stoney Street, Borough Market, 020-7403 7436, elliotscafe.com) is a bright, hip eatery about 10 minutes' walk away. It offers an exciting array of regularly changing dishes from about £5, shaped by what's available in the market – think terrines and fresh, interesting salads alongside heartier fare. You eat around a big communal cast-iron table, which is fun, although it can mean space is a little limited if you're with a brood. For somewhere a bit more family-friendly, The Table (83 Southwark Street, 020-7401 2760, thetablecafe.com), a modern canteen-style cafe that serves excellent brunch (try the knockout sweetcorn fritters at £10) until 4pm on Saturdays, is a good bet. The Refinery (110 Southwark Street, 0845 468 0186, therefinerybar.co.uk) is also a winner, with great sharing boards and a robust selection of salads. Mains around a tenner. If you just want a drink, its cocktail menu is one of the best in the area.

Harrods

If you're looking for a little haven away from the tourist throngs around Harrods, Zia Teresa (6 Hans Road, 020-7589 7634, ziateresa.co.uk), a charming, family-run Italian is it. There's no haute cuisine here, but it's the better for it: the food is fresh, the portions generous and the house speciality, piccantina siciliana (veal in a sharp, sweet orange sauce, £16) is a thing of sticky wonder. Everyone needs a drink after being in Harrods for too long, and the bar at A-list restaurant Zuma (5 Raphael Street, 020-7584 1010, zumarestaurant.com) is the perfect place to sit with a cocktail and watch the movie stars and supermodels flock into the restaurant. And what cocktails! There is a mind-bending selection of spirits available, including 40 varieties of sake, and unpronounceable Japanese-themed libations. Small plates from the Zuma kitchen are also available.

London Dungeon

Bermondsey Street, a mere five-minute walk from the Dungeon, has become a foodie mecca over the past few years. José (104 Bermondsey Street, 020-7403 4902, josepizarro.com/restaurants/jose), an intimate tapas bar run by chef José Pizarro (previously of the mega-successful Brindisa chain) is a must-visit. It doesn't take bookings, but the top-quality food (around £5 a dish) is worth any wait. Order from the specials board for dishes such as fresh-off-the-boat sardines on toast or grilled razor clams, washed down with a glass of excellent fino sherry. If you can't get in there, he's just opened a bigger place, Pizarro (194 Bermondsey Street, 020-7378 9455, josepizarro.com/restaurants/pizarro) offering similar small-plate fare (starters around £6, mains £15) just down the street. Then there's Zucca (184 Bermondsey Street, 020-7378 6809, zuccalondon.com), acclaimed chef Sam Harris's hugely popular modern Italian restaurant, offering terrific, unfussily presented food that won't warp your credit card (starters around £5, mains £15). It's almost worth going for the bread selection alone.

London Eye

Sweeping views across the river make Skylon Grill (Southbank Centre, Belvedere Road, 020-7654 7800, skylon-restaurant.co.uk/grill) the best choice of restaurant for maintaining the buzz of being on the London Eye, and the food's not bad either. It's the less-fussy offshoot of the fancy Skylon Restaurant and by far the better option for a relaxed meal, offering pre-theatre meals for £22.50. Eat from the grill (steaks, spatchcocked poussin, lemon sole) or choose from an all-day menu of dishes such as roast cod with chickpea and chorizo ragout. Burgers are exemplary, too, as is the kid's menu.

Westminster

For £25 (for three set courses), you can enjoy a fantastic lunch at the Northall restaurant in the grand Corinthia Hotel (10 Northumberland Avenue, 020-7321 3100, thenorthall.co.uk). The room is a show-stopper: ceilings high, tables immaculately dressed and the best-of-British food affordably luxurious. The nearby Royal Horseguards hotel (2 Whitehall Court, 0871 376 9033, guoman.com), has a great Anglo-French restaurant, One Twenty One Two (named after Scotland Yard's old phone number), with two courses for £15 at lunchtime, and a lovely terrace. For something less formal, take a short, scenic walk to St James's Park and Inn The Park (020-7451 9999, peytonandbyrne.co.uk/inn-the-park/index.html). You can't miss it – it resembles something between a Swiss ski chalet and a potting shed. The menu is simple, with a strong focus on British produce.

Trafalgar Square

Terroirs (5 William IV Street, 020-7036 0660, terroirswinebar.com) is the best lunch spot around here. Its simple, smart French cooking – terrines, rich stews and hearty salads – allows quality ingredients to shine. Its a small-plates affair (from £6 each), so you can easily nip in for a nibble. You should book at peak times, but if you show up for an early lunch midweek you'll almost certainly get a table. The wine list is extensive, and often cited as one of the capital's best. A five-minute walk into Covent Garden will bring you to da Polpo (6 Maiden Lane, 020-7836 8448, dapolpo.co.uk), restaurateur-of-the-moment Russell Norman's most recent Venetian bacaro joint. Like many places, it doesn't take reservations at dinner, but the small plates costing about £5 (think squid-heavy fritto misto, pizzette, meatballs and arancini) are worth a short wait in the bar. They do, handily, take reservations for lunch.

British Museum

You might walk straight past Abeno (47 Museum Street, 020-7405 3211, abeno.co.uk). Its plain frontage doesn't say much, but inside, you'll eat some of the best, most authentic Japanese food in central London. It's always full of young Japanese people who come for the Abeno speciality, okonomiyakis (savoury pancakes, from £8.50). The drill is simple: you pick your ingredients (pork, squid, bacon, prawns, vegetables, cheese) which are added to a batter base with ginger and spring onions before being entertainingly tossed around on a hotplate in front of you. Their yaki-soba noodles are also delicious. For a post-museum drink, try the terrace bar at the Montague Hotel (15 Montague Street, 020-7637 1001, montaguehotel.com). It's a classy yet relaxed old-school drinking den (tartan walls and soft leather armchairs) and does the best classic cocktails in the area.

British Library

The area around the British Library and Kings Cross is dominated by chain eateries and greasy kebab shops, but in the smaller streets there are some gems, like Sichuan restaurant Chilli Cool (15 Leigh Street, 020-7383 3135, chillicool.com). It's not for the faint-hearted: this is complex-flavoured, nose-to-tail eating with a serious chilli hum (mains from £6.80). If you've not eaten Sichuan before, expect tingly, numb lips from the Sichuan peppercorns. If you're in the area from Wednesday-Friday, the new Eat St Market (Kings Boulevard, behind King's Cross station, eat.st/kings-cross) has mobile merchants serving delicious food from around a fiver: banhi mi, slow-cooked pork yum buns and burritos. Walk your lunch off along the canal – Camden is 20 minutes away.

Science Museum/Natural History Museum /V&A

The great tapas (from £3.75 a plate) at Casa Brindisa (7-9 Exhibition Road, 020-7590 0008, brindisa.com) aside, the restaurants on Exhibition Road near the big museums can be a little uninspiring. Head round the corner to Le Bistrot at the Institut Français (17 Queensberry Place, 020-7589 9996, institut-francais.org.uk) - a smart, monochrome hideout that is more St Germain than South Kensington. A big self-service buffet (don't be put off) has delicious quiches, charcuterie, soups, patisserie and over 15 different salads, from £6.75. You can just pop in for a drink – there's a robust wine and spirit list. Watch out for the coffee: more than one cup and you'll sprout wings and fly home.

Oxford Street

Meat Liquor (74 Welbeck Street, 020-7224 4239, meatliquor.com), a burger joint just north of Oxford Street (a hungry skip from Selfridges) was one of 2011's most hyped openings. Nestled below an ugly car park, it ain't smart: exposed light bulbs and graffitied walls give a grungy Lower East Side feel. But that's part of the appeal – you will not get a better burger in London, full stop (from £7). Predictably, they don't take bookings, but hang around – it doesn't take that long to eat a burger. For something cleaner, head for Soho and Koya (49 Frith Street, 020-7434 4463, koya.co.uk), a tiny Japanese noodle house. Its speciality is udon (from £6.70), made on the premises the traditional way (kneaded by foot) and served either cold with dipping sauce, or in big bowls of delicious broth. Daily specials are brilliant: look out for "fish and chips" – tempura monkfish with lotus root chips.

Camden

If radioactive orange Chinese food isn't your thing, steer away from Camden Market for something to eat. The Crown & Goose gastropub (100 Arlington Road, 020-7485 8008, crownandgoose.co.uk), away from the main tourist crowds, is a good choice. Framed butterflies create a backdrop to a well-stocked bar with a great selection of British ales, continental beers and whiskies, and staff that favour 1960s psychedelia and soul on the music system. The food's decent, too – fish and chips £11, burger, salad and fries £10.50. If you're in the mood for something more exotic head over the road to Le Mignon (98 Arlington Road, 020-7387 0600) a great little Lebanese restaurant with mains from £9.50, and try its kafta khashkhash (minced lamb with herbs, garlic and spices, grilled on skewers).