Remove all skin from fillets, ensuring that no bones remain, and cut into serving size pieces. Chop the shallots, ginger, garlic, and chilies very finely, and pound these together with the turmeric, tamarind, and soy sauce.

Heat the oil in a shallow pan, and stir-fry the paste for 4 to 5 minutes, then add the fish; cover with approximately 1 cup of cold water and bring to a boil. Lower the heat, season to taste with salt and pepper and cook over a very low heat. Serve with fresh vegetables and rice.