Last week, we traced the origin of the word “curry” from its colonial roots to the skyrocketing numbers of curry houses in the UK. This week, we will examine about another distinct style of curry.

Until just 1939, Thailand was referred to as Siam. Although Siam had never been colonised by the West, its cuisine is heavily influenced by tis Asian neighbours. Think of the amazing Thai stir-fries, made in a wok just like the Chinese, but using its own distinctive ingredients like basil, galangal and fish sauce. Thailand has given this same unique treatment to our Indian curry as well, creating a rather unique style of dish called the Thai curry.

What distinguishes a Thai curry from its Indian or even British counterpart is the form in which all the complex flavours are introduced to the dish. Unlike Indians who use whole or freshly ground spices or the British who use powdered spiced blends out of a jar, the recipe for any self-respecting Thai curry begins with a paste, the heart and soul of the curry. However, there are some Indian dishes like the ghee roast which involves preparing a spice paste before the actual cooking starts, it is the exception rather than the rule.

Although Thai curries tend to get earmarked into the traffic signal colours of red, yellow and green, it is in fact a lot more versatile, and the curry paste can be made with anything you fancy. Just like an Indian curry, you’ve got onion, garlic and chilli and a couple of basic dry spices like cumin and coriander. A green curry paste gets its colour from a myriad of green ingredients. Some of these are familiar, like green chilli and coriander; the coriander root in particular is a must for an authentic green curry.

So, what else makes it green? There is Thai basil, more pungent that Italian basil and a crucial ingredient in Thai cuisine, from curries to stir-fries, although it is usually added to the curry at the end rather than being pounded into the paste. There is the incredibly flavourful kaffir lime whose zest has a complex citrus flavour comparable to but not similar to our very own gondhoraj lime. And finally, there is lemongrass whose citrusy, spicy notes lend brilliantly to curries, stir-fries and even dessert. Lemongrass and kaffir lime aren’t limited to a green curry, and lend a distinctive flavour to almost all of Thai cuisine.

Which brings us to two more crucial constants of Thai curries. Although similar to ginger, galangal root has a spicier, more peppery flavour, and the Thai prefer it to ginger in most of their cooking. Belacan is fermented shrimp paste, an incredibly potent ingredient whose flavour can put off a lot of squeamish eaters. It is usually roasted separately before adding to the paste and adds a distinctive flavour to all Thai curries. If you’re too squeamish or prefer a vegetarian curry you can skip this ingredient, but you’ll miss out on a lot of nuance.

Red curry gets its colour from dried or fresh red chillies, and yellow curry has yellow peppers a number of ground spices including turmeric, fresh or dried, lending the curry a distinctive colour, much like in Indian food. There are some other curry paste variants as well, like the famous Massaman curry which is probably closest to an Indian curry, with copious use of spices and a tangy hit of tamarind. There’s also the Panang curry, similar to but slightly sweeter than a red curry.

The paste is traditionally made in a mortar and pestle, with the harder ingredients going in first and the softer ones later. However, readymade pastes are a great weeknight hack, especially if all ingredients aren’t easily available. Once the paste is assembled, it is time to get cooking. You start off by adding some of the coconut milk to the pan, which splits and releases the fat, in which the dish gets cooked.

Let’s take a food science detour to talk about this “fat release” or “masale se tel chhorna”, shall we? When we add ingredients like onion, garlic and ground spices into oil, it forms a paste that incorporates the oil into it to form a stable emulsion, just like mayo. As we keep cooking it, the water content decreases relative to the fat, and once it reaches a breaking point when the relative fat becomes so much that the water can’t hold it anymore, the emulsion breaks, and the fat releases.

And why is this important? Because until most of the water is evaporated out of our spice paste, the temperature will not rise beyond 100 degrees Celsius. As we know, browning aka the Maillard Reaction occurs at much higher temperatures, which can only be reached when the water is gone, and the spices can start toasting in Maillard-land, developing complex flavours. The splo of fat is a visual indicator this crucial step, without which the curry sauce tastes flat and not enough cooked out or as your over-skeptical Bengali auntie would say, “bhalo kore koshano hoyni”.

Anyways, back to our coconut milk. Into the split coconut milk goes the curry paste, which gets fried in the coconut fat. Then goes in the protein, veggies, seasoning, and cooking liquid, either water or stock. Choice of protein can include chicken, prawn, beef or even tofu if you’re vegetarian. Much like a Chinese stir-fry or Indian vegetable korma, you can make do with whatever veggies you’ve got lying around, although some classics include the tiny pea aubergines, the golfball sized thai eggplant or apple aubergines, and punchy bamboo shoot. Then add in the rest of the coconut milk, season, and cook till done.

Like all of Asian cuisine, a good Thai curry has the perfect balance of salt, sweet, sour and spice, and a lot of that hangs of properly balanced seasoning. With the heat of chillies and the pungent notes in basil and lemongrass, we’ve got the spice sorted. For sour, the ingredient of choice is lime juice or even kaffir lime juice and tamarind pulp, as in a Massaman curry. For sweet, Thai people tend to replace refined white sugar for palm sugar, which adds a subtle molasses-like complexity apart from sweetness to the curry.

A major source of both salt and umami in a Thai curry is our old friend belacan, an integral component of the curry paste. When it comes to seasoning, the quintessential ingredient is the rather polarizing fish sauce, also popular in Vietnamese cuisine, made from salted fermented fish. It has a strong, off-putting smell, but is jam-packed with umami, and can amp up any dish it is added to. (“smells like feet, tastes like meat”, as the great Adam Ragusea puts it) Soy sauce could be used as an alternative, but the two are definitely not interchangeable.

After the curry has been satisfactorily seasoned, the meat and veg are cooked and the sauce reaches the right consistency, take it off the heat, garnish, and serve. The light, flavourful broth is ideal to be mopped up with steamed rice, often with a pandan leaf thrown in for flavour. Thai curry with rice is a perfect example of the yin-yang balance, a controlled complexity which is difficult to put into words.

Of the three curries in our series, the Thai curry is possibly closest to the Indian style in terms of complexity of flavour. If the Thai curry paste takes things to a whole new level of complexity, our next style brings it down to an almost ridiculously simple level, arguably beating the British curry powder by a mile in terms of accessibility and convenience. Join us next time as we conclude our curry trilogy.