Wash the yardlong beans thoroughly and slice them into 1-inch pieces. Chop the tomatoes and set aside.

In a mortar and pestle, crush the garlic and dried chilies into a smooth paste.

Transfer the chopped yardlong beans to the mortar and lightly pound them to bruise without mashing.

Add fish sauce, fermented fish sauce, tamarind paste, and palm sugar to the bruised beans and pound into a syrupy consistency.

Squeeze fresh lime juice into the mixture, toss in the chopped tomatoes, and mix well.

Taste and adjust seasoning with more lime juice or palm sugar as needed.

Transfer to a serving bowl and serve immediately.