Green curry has not aged well on these damp and chilly shores. Like many of us, it's thickened a bit over the years, and lost its edge. No longer the zingy arriviste which first startled our jalfrezi-jaded taste buds with its arresting combination of sour, sweet, salt and heat, with typical British aplomb, we've Anglicised it into creamy, sugary comfort food. The best way to get reacquainted with the real thing is by giving the ready meals and the takeaways a miss, and getting back to basics in the kitchen.
The backbone of a green curry paste is, of course, the chillies which give it its colour – although, truth be told, most authentic pastes are more of a murky beige. As well as heat, you need something salty – shrimp paste, or fish sauce – and some aromatics, like lemongrass and galangal, as well as the shallots and garlic which give the curry pungency and depth. The other ingredients are, as we will see, up for debate.
Before you reach for the jasmine rice, however, a word of caution. A green curry is easy to make – a green curry paste is not. Or, at least, not in Britain, particularly if you don't live anywhere near an oriental grocers. Take it from Kasma Loha-unchit, Thai cookery teacher and author of the award-winning It Rains Fishes; "unless you have all of the fresh herbs and spices required to make authentic and traditional Thai curry pastes, you're better off using commercial curry pastes than trying to make do with ill-advised substitutes". This isn't necessarily a disaster however – there are some very good pastes out there, and it's what you do with them that counts.
The usual suspect
It was Nigel Slater who first turned me on to the idea of making my own curry paste. His thrillingly tangy, peppery recipe has impressed many guests over the years – what I didn't admit is that it's surprisingly easy to make. Lemongrass, chillies, garlic, galangal, shallots, coriander, lime leaves, lime juice, fish sauce and black peppercorns are whizzed into a "vivid, spicily fragrant slush" before being cooked with coconut milk, stock, green peppercorns and whatever protein you might fancy, and topped with a handful of coriander and Thai basil leaves. As usual, it's delicious – sour, spicy, and very definitely not comfort food.
Sweet and sour
My first brush with Thai food, however, came when Nigel was still a new boy at the Observer, and certainly outside my teenage ken, in the form of Keith Floyd, sweaty and magnificently manic, prancing around South East Asia with an unreliable gas stove. I'm disappointed to discover that he advocates using a paste in the accompanying book, until I consider the probable availability of galangal back in 1994.
Rick Stein's recent travels in the footsteps of Floyd seemed a good place to look for a substitute; although somewhat grandiosely named, Far Eastern Odyssey was an excellent series, and I'm keen to try out the recipe (pdf) he picked up at the Poj Spa Kar restaurant in Bangkok. As well as the chillies (a scant number, in my opinion – just 2, to Slater's 6), galangal, lemongrass, shallots and garlic, he calls for 3 makrut (aka kaffir) lime leaves, and a teaspoon of shrimp paste. Both ingredients should be available in big supermarkets; although you can't import makrut lime leaves fresh into this country, Waitrose sells them frozen as part of their Cooks Ingredients range, and they're also found in jars.
The intensely savoury shrimp paste is complemented by the fish sauce which Stein adds to the curry itself, along with coconut milk, lime juice and 2 tsp palm sugar. I like the sweet and sour quality this gives the finished dish, but feel it overpowers the flavours of the carefully made paste – despite the lime leaves and the lemongrass, it just doesn't taste as fresh as Nigel's.
The quest for the makrut lime
If ever a book made claims for itself, it's Madhur Jaffrey's Ultimate Curry Bible. Surely here would be a recipe to beat Mr Slater's – given to the redoubtable Madhur by the Oriental Hotel Bangkok, it certainly has more claim to 'authenticity'. I'm pleased by the number of chillies – a whopping 14 bird's eyes – but not by the sudden appearance of makrut lime rind, which takes me three days to track down.
Makrut limes are knobbly, warty little things much prized for their unlikely perfume, but sadly, thanks to the aforementioned import restrictions, they're impossible to buy fresh in this country (although I notice small trees are available for £25 online). After an exhausting tour of Chinatown's oriental supermarkets, and a trip out to a Thai specialist in Hammersmith, who look at me as if I'm slightly crazed, and recommend I purchase a paste instead, I finally discover some pickled peel online. Hallelujah!
The recipe also calls for 6-8 fresh coriander roots, which have a deeper, more intense flavour than the leaves. Indian and oriental grocers may sell them with the roots still attached, but if not, for every root called for, pound 10 bare coriander stems into a paste and then use in the same way. The paste itself is promising – a lovely vibrant green, thanks to all those chillies – but once I've added the required teaspoon of thick, dark tamarind paste to the pan, 1 tsp of palm sugar and 1½ tbsp fish sauce, it's sort of muddy looking, and much too sour. In fact, despite the lime zest and the lemongrass, it's hardly aromatic at all.
Fresh flavours
Thankfully, this is the only recipe I see that uses tamarind. It's also the last one to call for a reasonable number of chillies. The Blue Elephant chain of restaurants, serving "royal Thai cuisine" demands 24, and 2 tsp of roasted and ground coriander seeds. The results are spicy, but again, lack the in-your-face aromatic qualities I was hoping for.
I find the recipe from Rosemary Brissenden's encyclopaedic South East Asian Food, with its comparatively modest 20 chillies, more pleasing, because it contains no dried spices whatsoever, other than ½ tsp of ground peppercorns. This seems to gives the finished paste a fresh, startlingly hot flavour which sets it apart from the others.
Two tips
Brissenden also teaches me to allow the curry paste to cook in the oil from the coconut milk, rather than frying it first, as in many other South East Asian cuisines. According to Thai food blogger SheSimmers, curry sauces are supposed to separate – not only does it make them look more appetising to Thai eyes, but it indicates the paste has been correctly cooked.
She also makes a convincing case for making the curry paste in a pestle and mortar, rather than a food processor; "an electric blade will always chop rather than pound, no matter how finely it does so. Even though you may end up with very small particles in your paste, the flavours will remain 'chopped' and separate rather than merged. Pounding spices into each other one by one in a stone mortar and pestle does a more complete job of extracting all their oils and causes the old spice to absorb the tastes of the new, until the flavours are completely melded." I'm pleased I only read this after making her paste – but fortunately I'm given the chance to try it out in my final recipe.
Thai guru
For serious devotees of Thai cookery, there's really only one recipe worth bothering with. David Thompson, the first Thai chef to win a Michelin star for his London restaurant Nahm, is also the author of the only Thai work to merit a place in Observer Food Monthly's top 50 cookbooks, Thai Food. He is, quite simply, a guru for those of us struggling to tell our galangal from our gapi – and he advocates using a pestle and mortar. The paste does seem much more hom*ogenous, with fewer little bits and I'm grudgingly won over – once I've worked out the hard way that it's advisable to wear eye protection while crushing chillies by hand.
By this point, I thought I'd seen it all when it came to Thai ingredients, but no as well as all the usual suspects, he throws in a new one; red turmeric. This is the fresh root we more often see in powdered form; from experience, I can assure you, it's equally staining – my fingers look like those of a committed smoker for some days after cooking his recipe, but my word is it worth it. Strong, salty, spicy, rich and aromatic, Thompson's curry is as overwhelming and thrilling as a Bangkok street market. I omit the optional roasted coriander seeds, as I feel they interfere with the fresh flavour of the dish, and to make it absolutely perfect, I add half a teaspoon of palm sugar as a counterpoint to the savoury notes of the shrimp paste, which rounds things out nicely.
The best green curry pastes take no prisoners. They should be made by hand, with more chilli, lemongrass and shrimp paste than you think strictly wise, and cooked carefully – then you'll remember why you fell in love with Thai food in the first place.
Perfect Thai green curry
Serves 2
For the paste (or use 4 tbsp of good quality bought paste like Thai Taste's):
20 bird's eye chillies
1 tbsp chopped galangal
3 tbsp chopped lemongrass
1 tsp makrut (aka kaffir) lime zest, or 2 tsp finely minced makrut lime leaves
1 tsp chopped coriander root, or 10 tsp pounded coriander stems
1 tsp chopped red turmeric
2 tbsp chopped shallots
2 tbsp chopped garlic
1 tsp shrimp paste
Ground white pepper and salt
For the curry:
5 tbsp coconut cream
1 tsp fish sauce
½ tsp palm sugar
180ml chicken or vegetable stock
180g chopped chicken, seafood, pork or tofu
100g pea aubergines or chopped purple aubergines
2 makrut lime leaves, shredded
3 red chillies, deseeded and finely sliced
Handful of Thai basil leaves
1. Pound the paste ingredients one by one in a pestle and mortar, making sure each is well incorporated before adding the next. You can use a food processor, but you won't get quite such good results.
2. Heat the coconut cream in a small saucepan, and allow to come to the boil. Once it has reduced and begun to split, add 4 tbsp curry paste and mix, stirring continuously until aromatic – taste to see whether the spices are cooked.
3. Add the fish sauce and sugar to taste, pour in the stock and bring back to the boil, then put in the meat or tofu, and the aubergines. Simmer until cooked through, then stir in the lime leaves, red chilli and basil leaves. Stir in a little more coconut cream if it's too spicy, and serve with jasmine rice.
