Marinate the fish fillets for about 1 hour in combined white wine, lime juice and some black pepper, and 1 garlic clove (this step is optional if you are in a hurry - just add the lime juice and basil to the tomato sauce if you omit it).
Using a large diameter fry pan, fry the onion and garlic in a little oil until soft. Add the chopped parsley, tomatoes and vermouth, bring to a bubble and simmer for a couple of minutes. Season with salt/pepper to taste. Place the fish fillets on top of the sauce, spoon a little of the sauce on top of the fillets and cover. Simmer over a low heat until fish is cooked through (5 to 15 minutes, depending on the thickness of the fillets). Serve fillets on a bed of rice, spoon the tomato sauce over and serve with a tossed salad.
(I can only comfortably fit 3 fillets in my fry pan - if you have more, transfer the sauce to a large baking dish, add fish fillets, cover with foil and bake in pre-heated moderate oven (350°) until cooked through)