Finadene

Finadene is a salty, spicy, soury condiment found on every fiesta table. the sauce not only provides an added 'kick' to whatever it is added to (rice, barbecued meats, grilled fish--anything, really), its acidity adds a freshness to items that can seem stodgy or greasy otherwise.

Many households have a jar of finadene on the table anyway, but the basic sauce of 1 part soy sauce, 1 part vinegar, chopped white onion and fresh chilis is usually taken to a new level for fiesta time.
The usual addition is fresh lemon, lime, dayap, or calamansi juice; also, green onions, thin slices of lemon, or halved cherry tomatoes are added for extra zing. I happen to use all of them (plus a little sugar to tone down the acid).

Not only is it an excellent condiment, it is a good marinade for meats and fish for grilling, and i use it as a steaming liquid in a superquick fish dish: in a microwaveable glass dish, lay down several small coins of cut fresh ginger; the ginger doesn't always add flavour to your dish (esp. if you leave the skin on), but it is important because it neutralises any fishy smells which frankly, are rank, and i can do without. Place one fillet of fish of your choice (defrost if frozen) on top. drizzle fish with finadene slightly diluted by water, cover dish with clingfilm, zap on high for 2 minutes, and dinner is served. (scentofgreenbananas.blogspot.com)