Dice the potatoes and Spam into bite-sized cubes.

Blanch the Spam in boiling water with a bit of vinegar to reduce saltiness. Alternatively, soak it in hot water with vinegar.

Add water, soy sauce, and tuna fish sauce to the potatoes and simmer until partially cooked.

Add the Spam to the pot and continue simmering until the potatoes are fully cooked.

Add plum syrup and simmer until the liquid reduces. Add green and dried red chilies and cook briefly.