Prepare the curry paste ingredients: peel the shallots and garlic, and scrape the peel of the fresh turmeric. Use both fresh and dry chilies, preferably of different varieties to create a more complex chili flavor, hat and aroma. Use high quality fermented shrimp paste.
Pound all the ingredients using a pestle and mortar, starting with the chilies and salt, into a consistent paste. Mix in the kapi.
Dilute the curry paste in simple fish stock or water.
Add Asam Gelugur, and start boiling the curry.
When the curry is still lukewarm, season it with palm sugar.
Add fish sauce.
Season with tamarind paste.
Mix well and taste, adjusting as needed. The curry should be spicysour and salty, with a faint sweetness, and a pleasant bitterness from the turmeric.
Let the curry boil. While cooking the curry paste, don’t rush to skim off the crust that forms or you will lose flavors; wait until the curry is cooked before skimming.
Add an extra dose of ground dry chili powder we want it really spicy!
Add lotus stems, cut into 2.5 cm (1”) slices.
A couple of minutes later, add the thicksliced fish, ensuring that the fish is at room temperature. Immerse the fish completely into the curry broth and make sure that the broth is boiling – this will prevent a fishy odor.
When the fish is cooked, turn off the heat and squeeze in a generous amount of lime juice.
Serve along with fried steam mackerel, Thai crispy omelet, salty beef jerky (neuua khem, เนื้อเค็ม), lightly salted and deepfried snakeskin gourami fish (bplaa sallit, ปลาสลิด), sundried snakehead fish, sundried squid etc.