Cook the potatoes (uncovered) in boiling salted water over a medium heat for approx. 20 mins. until soft. Drain the potatoes, return to the pan, mix in the oil and herbs, season, keep warm.
Heat a dash of oil in a non-stick frying pan. Season the fish fillets, fry in batches for approx. 2 mins. on each side, keep warm.
Cherry tomato sauce
Cut the onions in half. Heat the oil in the same pan. Stir fry the onions and ginger for approx. 2 mins. Add the cherry tomatoes, season with salt, cover and cook for approx. 4 mins., add the basil. Drizzle the sauce over the fish, serve with the herbed potatoes.