In a large non stick frying pan saute lots of garlic and sliced a good amount of sliced onion with a splash of olive oil till golden brown.
Add a large fillet or a few smaller fillets of chilean sea bass and immediately add a good splash of white wine, enough to cover the onions .Reduce the wine by 50%. Shut off flame and leave the fish covered.
Cut a good amount of fresh tomato. Drain a couple of tablespoons of capers and a good handful of pitted gaeta olives.
Add tomatoes capers and olives to fish, and put the flame back on high until it begins to boil, season with salt / pepper fresh basil.
Gently remove the fish and place in a baking pan. Pour the semi cooked tomato mixture over the fish and cover with aluminum foil. Preheat oven to about 375 and bake about 25 minutes or more. No worries about over cooking the fish in case you need to go 30 minutes or a bit more.Chilean sea bass holds it form and texture when preparing it "stewed style" and stays super tender.
Serve with rice or boiled potato and salad.
Turn left overs into a delicious pasta sauce ; separate the fish from sauce , simple heat sauce, break up the bass into bite size , add cooked pasta and toss . Top with fresh basil or parsley and a bit of hot pepper.