Cook the beans. Add 3 tablespoons of oil to a medium pot over high heat. When the oil starts to ripple, add the rempah paste. It should bubble immediately. Fry the paste on high heat for 2 minutes, scraping the bottom of the pot to prevent the paste from burning. After 2 minutes, lower the flame to medium and continue cooking for another 15 minutes, stirring constantly to prevent burning. The goal is to bring out the umami of the garlic and shallots without burning the natural sugars in them. The paste is done when it takes on a jammy consistency and separates from the oil.
Add the soaked beans, salt, and 2 cups of water. Increase the heat to high, bring the pot to a boil, then lower to a simmer. Partially cover the pot with a lid (you can use a ladle or large wood spoon to prop the lid slightly open). Cook until the beans are tender, 1 hour to 3 hours.
Once the beans are tender, stir in the palm sugar, coconut milk, and makrut lime leaves and increase the heat to high. Once it comes to a boil, reduce the heat to low and simmer for a final 10 minutes. Taste and add a little more salt if you’d like.
