- Place the fish on a rack in a roasting pan.
- Fill bottom of pan with water up to the rack.
- Spread the Onion mixture all over the fish.
- Simmer or bake at 350°F for 30 to 40 minutes or until fish is done.
- Remove the lid and permit the water to evaporate or reduce by one-quarter.
- Remove the fish carefully to a large platter.
- Spread the Onion mixture over the top of the fish as a garnish.
- Serve fish with rice at the side, with the sauce, and with lemon slices.