Food - specifically Thai cooking - should be one of the highlights of any visit to Bangkok. There are thousands of restaurants to choose from, but if you don't try Bangkok's street food, cooked to order, usually over a fierce flame in a wok, you are missing out. So how do you choose where to go?

Picture gallery: How to get the best from Bangkok's street food

I have just been on a tour of Bangkok with Chawadee Nualkhair, or 'Chow', as she appropriately likes to call herself. Chow is a Thai brought up in the USA who returned to Bangkok as an adult and developed a passion for street food.

She writes a blog and has published a book about the top 50 places to grab a bite along the road. We managed eight places, until we were too stuffed to walk.

Sukhothai noodles at Somsong Pochana

First, to Banglamphu, in old Bangkok.

This area is popular with tourists, particularly around Khao San Road, but it also has some of the best casual eating spots in the city.

They pay attention to detail- the balance of flavours, texture, aroma, how it feels on the tongue Chawadee Nualkhair, Food blogger

Chow took me to Somsong Pochana, near the Chaophraya River, which is renowned for its Sukhothai noodles.

These are thin rice noodles, in a pork broth sweetened with palm sugar, tamarind, slices of pork, crunchy green beans, topped with peanuts. I asked Chow what was the key to getting this dish right.

"It's got to be spicy, but not overpoweringly, tart from the tamarind, sweet from the sugar," she says.

"Roasted peanuts for texture - you need to get the balance just right. That's what I love about Thai food. They pay attention to detail - the balance of flavours, texture, aroma, how it feels on the tongue."

The chef at Somsong Pochana also served me kanom jin saonam, an unusual and hard-to-find dish these days: fermented rice noodles, topped with coconut cream, masses of raw, sliced garlic, pineapple, chillies and dried shrimp. An amazing mix of flavours, but delicious!

Pork sate at Chongki

Next towards Hualampong Station, Bangkok's main railway terminus, for pork sate at Chongki.

Sate is a Malay/Indonesian dish, although of course as Muslims they use chicken or goat meat, rather than pork.

A row of young women sit in the corner of Chongki, quickly skewering the chunks of pork or liver onto thin bamboo sticks.

It's marinated in sweet coconut cream, grilled over a smoky barbecue, and dipped in a peanut sauce, the recipe for which is a secret closely guarded by Chongki.

Thais will tell you that all their food should have a balance of four flavours - sweet, salty, sour and spicy - and the sauce seems to have all these.

Nai Mong Hoy Tod

Real men, apparently, like their oyster omelettes soft and sloppy

We moved on, to a little café called Nai Mong Hoy Tod, just off Charoen Krung, the main road in Bangkok's Chinatown.

Hoy tod is one of many Thai street dishes with its origins in China - brought by the influx of Chinese immigrants a century or so ago.

It's an omelette, filled with local oysters or mussels, cooked on a hot griddle.

A wonderful snack, but like many casual Thai dishes, be sure to specify if you don't want the cook to put MSG in it. Even good cooks do this in many parts of Thailand.

Chow likes her omelette super crispy, which she assures me is a feminine trait.

Real men, apparently, like their oyster omelettes soft and sloppy.

Nam kaeng sai in Suan Luang market

If you are after dessert, there is nothing more cheerful than nam kaeng sai - shaved ice, piles of multi-coloured jelly bits, strings of dough, crunchy water chestnuts, ginko beans, with salty-sweet coconut cream on top.

And there is nowhere better to have it than Seng Sim Ee, in Suan Luang market, behind Chulalongkorn University. Don't be put off by the swarms of bees clustering around the bowls of ingredients - it is a richly refreshing dish, well worth the trip.

I asked Chow what she looked for in a street stall or restaurant.

"Hygiene is the first thing I check. Are the condiment jars clean? Have the tables been wiped? What about the food preparation areas."

I have been eating street food in Thailand for more than a decade, and I have never once had an upset stomach.

Hygiene standards may not seem to be up to top restaurant standards, but I suspect there is not much between them. The best street stalls do care a lot about keeping their cooking clean and safe.

Jok at Jok Samyan

Another dish that has come from China is 'jok' - rice porridge, or congee. And most Bangkok residents will tell you that the place to go is Jok Samyan, also behind the university.

Outside the café, a woman stirs an enormous pot of simmering rice that has been stewed to a sticky, soupy consistency. Next to her is an equally large pot of pork-bone soup. Thais like to add minced pork-balls, and a raw egg, with crispy bits of fried dough on top. It's irresistible - real comfort food.

"It's the quality of their meatballs - they're very well seasoned - that makes this restaurant so famous," says Chow.

Phad thai at Thip Samai

Few dishes are as well-known in Thailand as phad thai. This fried noodle recipe originates from an attempt by a nationalist Thai leader in the 1940s to give noodles - a Chinese import - a more 'Thai' flavour, by holding a competition. Phad thai was the result.

Cooked in a searingly-hot wok, the noodles are fried with bean curd, garlic chives, dried shrimp, then tamarind juice and palm sugar are added, and it is served with chillies, nam plaa - the ubiquitous fermented fish sauce - bean sprouts, banana blossom and coriander leaves.

At Thip Samai, back in Banglamphu, perhaps the most famous phad thai restaurant, they keep at least two woks going on charcoal stoves, producing a phad thai every minute.

Then, in a trademark twist, a woman coats another wok with egg, and with two flicks of her spatula, ingeniously wraps the noodles in a neat, egg bag. Like so much fried street cuisine, this is not health food, but it is irresistibly delicious.

Phad Kee Mao at Jay Fai

Round the corner from Thip Samai is one of the city's most famous street chefs, Jay Fai.

She's been called the 'Mozart of the Wok', and watching her stoking her charcoal stove to blast-furnace intensity, and tossing ingredients into a wok or saucepan with lightning speed, it is easy to see why.

The dishes at Jay Fai are more expensive than other street food. A plate of phad kee mao - 'drunken noodles' - will set you back US$10. But eating it is the closest to noodle heaven I have ever been.

Thick slices of chilli and onion, a rich, smoky gravy, succulent prawns and glistening noodles, all cooked in a matter of seconds. Perfectly balanced, wonderfully fresh. Her tom yam gung, sour prawn soup, is legendary, and priced to match.

Som tam at Hai Somtam

Finally, no Thai food odyssey would be complete without som tam, the fiery salad of grated, green papaya from Thailand's north-east. Among the best places to get it is Hai Somtam, in Soi Convent, just off Silom Road.

The papaya is pounded with raw garlic, chillies, fish sauce, lime juice, and small tomatoes, and for an especially pungent flavour, a raw, fresh-water crab is thrown into the mix. Eat with small baskets of sticky rice.

A true taste of Thailand, uncompromising and unmistakable.