Marinate skin of bangus in calamansi juice, soy sauce and ground pepper.
Boil bangus meat in slightly salted water, peppercorns, leeks and celery.
When done, drain, remove bones and flake. Set aside.
In part of olive oil, saute garlic, tomatoes and onion.
When onion is transparent. add mushrooms. Add sweet relish.
Let cook for a while, then add flaked bangus.
Taste seasoning, cover and let simmer for a while.
Add stuffed olives and egg. Mix well. Let cool.
Stuff mixture into marinated body.
Sew up around the neck then sprinkle bangus with flour. Preheat oven at 220°C.
Line a shallow pan with part of remaining olive oil.
Lay fish on it and bake for about 20 minutes, turning once, basting the top with remaining olive oil.