Fresh lemon grass, hot ginger, cool coconut ... Simon Hopkinson has returned from Bangkok with his chef's palate whetted It seems that a Thai restaurant opens every day somewhere in London. I could not be happier. It is a style of cooking that refreshes
Having first eaten Thai food at Chiang Mai, in London's Soho, I had always longed to taste the food at source. So it was with much excitement that I finally arrived in Bangkok for a three-night stay, en route to Australia.

It is a smoggy, smelly, hot and steamy city, with a traffic problem that beggars belief. But life and soul seem to be held together by food, the cooking of it, anywhere, any time, anyhow.

Stalls fill the pavements. It does not seem to matter one jot whether a rickety charcoal grill is only going to dispense maybe five or six servings of pork satay over a lunchtime, the vendor seems content. I was, too, and returned for a second helping.

It seems that a Thai restaurant opens every day somewhere in London. I could not be happier. It is a style of cooking that refreshes and perfumes the senses quickly and with vigour.

I can smell the frying and steaming from those street woks now; the fragrant whiff of lemon grass and lime leaf, the sting of chilli with pungent ginger and acrid coriander leaf, and the familiar savoury "eat-me" niff of fried onion and garlic. All this calmed by a constant river of sweet and cooling coconut milk.

These ingredients, along with the proteinaceous seasonings of kapee (dried shrimp paste) and nam pla (fermented fish sauce), seem to me to be the backbone of Thai cuisine.

While in Bangkok, I was invited to dinner at a place where the fare was far more sophisticated than that of the street vendors, but the vibrancy of flavour and freshness of taste were the same. One of the other guests was a charming fellow called Chalie Amatyakul, who used to be the chef of the renowned cooking school at the Oriental Hotel. He took me through some of the dishes he had chosen for dinner, in particular the curries.

One of these turned out to be remarkably strong both in spice and depth of flavour. Chalie explained: "The sauce here uses dried fish, where the stomach has been allowed to ferment."It was one of the finest things I have tasted. The other two curries both used duck; one was "thick and creamy" made with red curry paste, and the other a lighter, green curry that included fresh green peppercorns.

But what really differentiates these curries is chillies - red and green - and the thickness of the coconut milk. The red curry's thickness is achieved by letting the coconut milk cook until it almost separates, and clings to the meat. The green curry was "hotter", more aromatic and very liquid.

I met Chalie again two days later, when I was treated to an elaborate Thai picnic. There were strips of fish and prawn in wrappers that had been deep-fried, and with appropriate dips; crisp little disks of puffed rice on which to smear a hot and sweet sauce, peanut I think, and little hollowed-out towers of cucumber filled with a spiced and finely minced chicken salad. The dish is called laab gai. There is an almost identical version made with prawn.

But a discussion of Thai food would not be complete without a mention of the famous Thai condiment, nam prik. It is the ketchup of Thai tables, and a meal is unthinkable without it.

Nam prik is best when fresh. The ingredients are inexpensive so don't fret if you have some left over, It can be used the following day, but does not quite have the same zing. Use this for grilled or cold shellfish, grilled steak, chicken or lamb cutlets.

The dried shrimps, or paste, are essential, and one of the most common ingredients in oriental grocers, but if you cannot obtain either, the sauce is still quite good without them. I have used mashed up anchovies with some success. Don't be afraid of these unusual ingredients. Discovery is one of the most exciting aspects of cookery.

Nam Prik (Thai chilli sauce)

Enough for 4-5 as a dip

Ingredients: 2 tbsp dried shrimps, or shrimp paste

8 peeled cloves of garlic

4 dried red chillies - seeds removed or not, depending how hot you like it

11/2 tsp sugar

3 tbsp fish sauce

3-4 tbsp lime juice

2-3 fresh green chillies, seeded and finely chopped

Preparation: Process everything briefly in a food processor. Add a touch of water if it seems too stiff. Against all tradition, I like to add some coriander leaves too, but that's just personal.

Chalie's Recipe for Laab Gai Enough for 6 people nibbling

Ingredients: 450g/1lb cooked and finely chopped chicken meat

2-3 small and thin cucumbers, cut into 2 cm/3/4 in slices, centres slightly hollowed out with a teaspoon

1tsp shrimp paste

10 cloves of garlic, peeled and crushed

10 purple, Thai (or French) shallots, peeled and crushed

10 red chillies, dried or fresh; seeded or not

1tbsp finely chopped fresh galanga ginger or ordinary ginger, peeled, coarsely chopped

1tbsp fish sauce

1tsp palm - or ordinary - sugar

2 tbsp lime juice

2 tbsp finely sliced lemon grass - tender bulbous part

a few leaves of mint and or lime leaves, shredded

3-4 tbsp vegetable oil

Preparation: Dry roast in a medium oven, or non-stick pan, the first five ingredients until golden and toasted. Grind to a paste in a food processor. Add the second five ingredients and fry everything in the vegetable oil until "fragrant". Now add to the chicken, mix thoroughly and pile on to the cucumber cups. Garnish with coriander leaf.

`Roast Chicken and Other Stories' (Ebury, £17.99) by Simon Hopkinson, with Lindsey Bareham, has just won this year's Andr Simon Award.