Mix the pork with
Pound all the paste ingredients in a mortar with a pestle until you have a fine paste. Or process with a blender, adding
Heat a wok until just smoking. Add the oil and, when hot, stir-fry the pork in batches until golden, then remove. Put the paste into the wok and stir-fry over medium heat for about 5 minutes, or until fragrant. Add the palm sugar and let it caramelise slightly, then add the remaining fish sauce. Return the pork to the wok with the beans, then stir-fry for another minute before serving.