Heat oil in a non-stick frying pan on high. Place fish skin side down and cook for 3 minutes, until skin is golden and crisp. Turn to cook other side for 2 minutes, until golden and cooked through. Remove from pan and keep warm.
Cook garlic in pan for 10 seconds, add tomatoes and cook for 2 minutes. Add white wine and olives and bring to boil. Add basil and season to taste.
Serve fish with tomatoes and sliced potatoes. Drizzle with sauce and serve.