Heat the olive oil in a pan over medium-high heat. When hot, add the shallots and the pepper. Cook for 2 minutes, stirring occasionally.
Stir in the garlic, and all the tomatoes, olives, and oregano. Cook for a further 5 minutes, stirring frequently.
Add the vermouth and bring to a simmer. Season with salt and pepper, and reduce until the sauce thickens. Remove from the heat. Set aside.
Meanwhile, heat the extra oil in a heavy-based frying pan. Cook the fish fillets skin side down for 4 minutes. Turn them with care and cook for an additional 2-4 minutes until they are clear-looking and flaky.
Portion the fish into serving plates. Pour a little of the sauce into each portion. Follow with the parsley.
Serving Suggestions: Serve with potatoes, vegetables, rice, bread, or pasta.