I don't really like plain white fishes so I did this ....
In a big pan - less than one tbsp olive oil and sliced onions.
When the onions are soft, drizzle in a bit of lemon juice.
When that is all bubbling set fish fillets on top add pepper and let cook until fish is falling apart.
That's all!
You get all the goodness of the fish and onions are a great vegetable!