Here is our recipe for rempah fish—a Penang Nyonya specialty that is well-loved by many Peranakan/Nyonya-Baba families. If you go to Penang, you might find it at economy rice stalls if you are lucky!
Clean and rinse fish with water. Using a sharp knife, cut a deep slit from the back of the fish along the bone. Repeat the same on the other side of the fish.
Blend the spice paste with a mini food processor or use mortar and pestle to pound the flavoring paste.
Heat up wok with 3 tbsp oil, add in spice paste and stir-fry with low heat until aromatic. Add tamarind juice and continue to stir-fry until the spice paste is smooth and somewhat moist, but not overly runny. Season to taste with salt and sugar. Dish out and let cool.
Stuff the spice paste into the fish on both sides of the slit and also inside the fish stomach.
Heat up 1/4 cup oil in a wok, deep fry the fish until cooked. Serve immediately.