I use cod roe for my version of deviled eggs. Cod roe adds them a pinkish appetizing color! You can find cod roe at a Japanese food store. Be careful when you add salt to the yolk mixture because cod roe is very salty. Maybe you don't need salt at all.
Preheat oven to 350 degrees F (175 degrees C). Wrap cod roe with lightly oiled aluminum foil. Bake for 20 minutes.
Place eggs in a saucepan, and add enough cold water to cover the eggs. Bring it to boil, cover, and then remove from heat. Set aside for 12 minutes. Drain, and pour cold water over the eggs to cool them. Remove eggshells, and slice the eggs in half lengthwise.
Place yolks in a mixing bowl, and mix with cooked cod roe and butter. Season to taste with salt. Spoon the yolk mixture onto the egg white halves. Sprinkle minced parsley on top, and serve.