Plaa som ("sour fish") is usually associated with a type of whole fermented fish popular in NE Thailand. As much as you all love rotten fish, it's unfortunately not what I'm going to be making for this lesson. Today's plaa som is actually a southern dish that takes a hearty Spanish mackerel steak, fries it until cripsy, and coats it with a sour, chili-based sauce.
You'll need a spanish mackerel (plaa insee) steak of about 200-300 grams.
And, as usual, you'll need to make a curry paste:
Large dried chilies (soaked in warm water until soft) 5
Salt, 3 tsp
Garlic, 10 (small) cloves
Shallots, 3
Other ingredients
Sugar, 1 1/2 Tbsp
Vinegar, 1 1/2 Tbsp
Water, 1/4 cup
Onion, 1/2 sliced
Ginger, one medium root, chopped
Using a mortar and pestle (or food processor) grind the chili paste ingredients up finely. Set aside.
Chop your ginger and onion.
Combine the sugar/vinegar/water mixture. Set aside.
Taking your mackerel steak, rub a bit of salt into it (this helps to prevent it from sticking to the pan), and fry it in a generous amount of oil until crispy and somewhat golden.
Remove fish and let drain. Remove all but about 1-2 tablespoons of the oil, and add the curry paste ingredients. Fry until blended and fragrant.
Add onion and ginger, and fry until onions begin to soften.
Add sugar mixture and fry, stirring constantly, over medium heat until slightly reduced. Add more water if the sauce becomes too dry, and continue cooking until sauce is reduced somewhat.
Put fish on plate and cover with the onion/sauce mixture.
Done.