Step 1 Heat the oven to 400 degrees. Season each fillet with one-eighth teaspoon salt and a small pinch of pepper.
Step 2 Place the fillets in a large, oven-proof saute pan along with the broth and bake for about 10 minutes until cooked through. Remove the pan from the oven and reserve the fish, discarding the vegetable broth.
Step 3Warm the olive oil in the saute pan. Add the tomatoes, scallions, capers and basil.Cook over medium heat, stirring gently. Do not bring to a boil.
Step 4When the tomatoes are warmed through, add the olives and vinegar. Season with one-fourth teaspoon salt and a pinch of pepper, or to taste.
Step 5Place one fillet on each of four plates and spoon the sauce evenly over the four fillets. Serve immediately.