The keen-eyed among you may have noticed that the fish in the photograph isn’t, in fact, lemon sole, but plaice. The simple truth is that it’s what they had at the fishmongers, though at the moment lemon sole is actually a more sustainable choice.
Plaice enters its breeding season in January and should be left in the sea to do its thing for a few months. Of course, any small flatfish would work here – even a couple of dabs per person, should you find them. They are usually ridiculously cheap. Just reduce the cooking time accordingly.
There’s no seasonality issue with cavolo nero at this time of year, of course. January is prime cabbage and kale territory – they are one of the few things that actively thrive in the cold and wet of a British winter. If black kale proves elusive, you could happily make this with savoy cabbage instead.
Extra virgin olive oil
Fine sea salt and freshly ground black pepper
4 whole lemon sole, cleaned and trimmed (head on or off as you wish)
A splash of white wine
400g cavolo nero, stems remove and discarded
1 medium onion, finely chopped
2 cloves garlic, crushed
6 anchovy fillets (the salted, brown sort) in olive oil, drained and chopped
150ml double cream
Up to ½ fresh nutmeg, grated
A couple of pinches of cayenne
Heat the oven to 200C / Fan 180C / Gas 6. Splash a little olive oil over the bottom of a roasting tin large enough to hold all the fish and rub over the bottom using a bit of kitchen paper. Sprinkle with a little salt and pepper.
Roughly chop the cavolo nero leaves and plunge into a big pan of lightly salted boiling water. Cook for 3-5 minutes, or until tender. Drain, keeping back a cupful of the water. Put to one side.
Using a sharp knife, make 3 slashes in the dark-skinned side of each fish. Place in the roasting tin and season the top. Rub with a little olive oil, then add a splash of white wine to the tin. It’s just to stop the fish sticking and create a bit of steam – a few tbsp will be fine. Use water if you don’t have wine.
Place in the oven and cook for 12-15 minutes, or until the flesh is just cooked through to the bone.
While the fish is cooking, heat the olive oil in a large pan. Add the onion and garlic and sweat for 7-8 minutes, until soft but not brown. Stir in the anchovies until they dissolve into a rough paste.
Pour in the cream and bubble until slightly thickened, then add the cavolo nero, season with nutmeg, cayenne and a few grinds of pepper. Stir together and bubble for a minute or so more. If the sauce seems too thick, add a splash or two of the cavalo cooking water to think and bubble together until the liquids have combined.
When the fish is done, remove from the oven and put onto warm plates. Leave to rest for a couple of minutes, then spoon some of the creamed kale over the top. Finish with a trickle of olive oil before serving. Some sort of potato would be good alongside – maybe even a rustling bowlful of chips.