Roast whiting with brown shrimp butter and fat chips

Method

1. Put the fish fillets on a large plate and sprinkle with the salt. Chill, uncovered, for at least an hour – this will draw out some of the excess moisture and help firm up the fish. Brush off the excess salt and dry with kitchen paper. Chill.
2. Prepare the shrimp butter. Peel the shrimps (you’ll need 150g peeled weight) and set aside, reserving the heads and shells. Pour the wine into a saucepan, add the shallots and the reserved shrimp shells and heads and bring to the boil. Simmer for about 5 minutes or until reduced by three-quarters. Strain, return to the pan and set aside.
3. Preheat the oven to 220°C/fan200°C/gas 7. Partly cook the chips. Fill a deep, heavy-based saucepan about one-third full with sunflower oil and heat to 120°C (to test the temperature, drop a piece of bread in – it should take about 1 minute to brown). Using a chip basket or large slotted spoon, carefully drop a generous handful of chips into the hot oil and cook for 5 minutes or until tender but not brown. Remove from the pan and repeat, in batches, with the remaining chips. Remove the pan from the heat.
4. Put the flour and thyme in a shallow dish, season and stir. Add the fish and coat well, shaking off any excess flour. Heat the olive oil in a frying pan over a high heat. Add the fish, skin-side down, and cook for 1-2 minutes to crisp the skin. Transfer to a roasting tin, skin-side down, scatter with the lemon zest and roast for 5-8 minutes or until cooked through.
5. Meanwhile, return the saucepan of oil to the heat. Increase the chip oil temperature to 190°C (a piece of bread should take 30 seconds to brown). Return the chips to the oil, in batches, for 2 minutes, until golden and crisp. Drain on kitchen paper, sprinkle with salt and keep warm.
6. To finish the shrimp butter, slowly whisk the butter into the wine reduction over a low heat. Add the shrimps, lemon juice and herbs. Transfer the fish to 4 plates, spoon the hot shrimp butter over the top and serve each with a bowl of chips.