The strong, aromatic presence of onions and black olives works a treat with well-flavoured fish and they give this dish a lovely Mediterranean feel. I often make this with mackerel fillets, but the suggested swaps are all good choices – from a sustainability angle too.
Serves 2
3 tablespoons olive oil
2–3 large onions, finely sliced
3–4 bay leaves (optional)
A sprig of thyme (optional)
75g stoned black olives, roughly chopped
50ml white wine
Fillets from 2 medium mackerel or gurnard, or 1 small sea bass
Heat the olive oil in a large frying pan over a medium heat. Add the onions, with the bay leaves and thyme, if using, and stir well to break up the onion slices. Once they are sizzling, turn the heat down low. Cook very gently, stirring from time to time, for 20–25 minutes, until the onions are very soft and golden. You can cover the pan if you like, for part of the cooking time, to help them sweat rather than brown.
Add the olives and wine to the pan. Turn up the heat to medium and cook for about 10 minutes until the wine has evaporated. Season with salt and pepper. Push the onions to the edges of the pan to make space for the fish in the middle.
Lay the fish fillets in the pan, flesh side down. Turn them over after a few minutes to cook the skin side, spreading the onions over the fish to help the heat penetrate. They should be cooked through in about 8 minutes.
Grind some pepper over the fish and serve hot, straight from the pan, or at room temperature, with new potatoes or couscous.
SWAP Fillets of red mullet are also delicious cooked this way.