Chop off the roots and the first few inches of the stalks of the water spinach, discarding them. Remove any yellow or bruised leaves and rinse the remaining stalks under running water. Chop them into 3-4 cm pieces and set aside.

Peel the garlic and remove the stems of the red Thai chilies. Using a mortar and pestle, roughly pound the garlic and chilies together until you have a fragrant paste. Set this mixture aside.

In a pan over medium-high heat, add olive oil and allow it to heat for about 1 minute or until it shimmers slightly.

Toss in the minced garlic and chili mixture, stirring frequently for around 2 minutes, until fragrant but not browned.

Immediately add the chopped water spinach to the pan, stirring for about 2 minutes, or until the spinach is slightly wilted yet still bright green.

Finally, drizzle in the oyster sauce and fermented soybean paste. Continue to stir, ensuring every leaf is coated, for another 2 minutes.