2teaspoonsgalangalpeeled and finely diced. If you can’t find galangal, use ginger in the same amount
2stalkslemongrasseach about six inches long. Get some crush onto the stalks by smacking them a few times with the back of a heavy knife. Then cut the stalks into two-inch lengths
10lime leavesroughly torn into ½-inch pieces
2tablespoonspalm sugarchop the solid sugar into pieces so it’ll dissolve easily
Partly cooking the prawns – hot and fast in butter
Melt the butter in a big skillet over high heat. As it starts to foam, add all the prawns and fry for 90 seconds before turning them and frying for another hot 90 seconds. Take the skillet off the heat and remove the prawns – they’ll be joining the soup’s broth toward the end of its cooking. You’ll also be de-glazing the skillet with a little of the broth to capture every last drop of that prawn-shell flavor.
Cooking the rice
Best here to follow the instructions on the packet and cook for maybe a couple minutes longer to achieve a slight stickiness. Once it’s cooked, put it into a warmed serving bowl, cover it and put the bowl into a very low oven. Maybe with a good lump of butter on top to slowly melt into the rice.
Cooking the broth
Fill a good-sized pot with the water and set it on a high heat. Add the chilies, lemongrass, garlic, galangal, lime leaves, palm sugar, lime juice, and fish sauce. Bring the pot to the boil and then immediately turn the heat to low so that it runs at a gentle simmer for fifteen minutes. Lemongrass is a pretty woody, fibrous plant and this simmering is needed to bring out its scented flavor. It will also soften the lime leaves.
After that simmering, taste the broth to check if it’s salty enough. The natural salinity of the fish sauce might have done the trick, but if not, add some ground sea salt to taste. It’s now that I’m also looking to rate the broth’s chili-heat. If it’s lacking some punch in that department, add some more diced Thai peppers. Hot. It’s gotta be hot.
Finishing the tom yum
Keep the pot on a low heat and add the thinly sliced ribbons of chicken breast to the simmering broth. Let it simmer away for two minutes before adding the sliced bok choy. Stir the pot and let it all cook for another two minutes.
Whilst that’s happening, use a few tablespoons of the hot broth to de-glaze the prawns’ skillet and then add all that liquid to the simmering pot. No stock cube required.
Now add all the prawns and their plate-juices. Turn the heat under the pot to high. As soon as the broth starts to boil, turn off the heat and stir in the finely chopped cilantro.
Let the tom yum soup sit for a minute before giving it a final stir and serving it in big, warmed soup bowls, with the sticky rice in small bowls on the side.
Notes
On cooking the prawns: You’re looking to get some color on the prawn shells and to pull out the shells’ particular flavor. It’s that shell-and-butter combo which acts as a substitute for any type of fishy stock cube.For drinks, I’d go for an icy-cold, pale, light lager. The famous Thai brand, Singha, would be grand but a crisp lager of your choice will be just fine alongside the seriously spicy kick of the tom yum.Final word on the lemongrass – it’s there for flavor only. Best not to try and eat it.