Langoustine and Salmon Tart

This is a more sophisticated version of salmon en croute

with a rich langoustine sauce to serve.

Ingredients:
For the langoustine tart:
500g all-butter puff pastry
600g salmon, skin and pin bones, about 2.5cm/1in thick
1 egg white
50ml double cream
20 langoustines, peeled, de-veined, shells reserved for the sauce
125g baby spinach leaves
2 egg yolks, beaten

For the sauce:
50g butter
1 onion, roughly chopped
1 carrot, roughly chopped
½ head fennel, roughly chopped
2 sprigs fresh thyme
2ml cayenne pepper
10ml tomato purée
75ml white wine
500ml fish stock
75ml double cream
½ lemon, juice only

Method:

For the tart, preheat the oven to 200C.

Roll the pastry out on a floured work surface to a 3mm thickness. Cut out a 30cm x 10cm rectangle and a 37.5cm x 15cm rectangle.

Trim the salmon into a 27.5cm x 7.5cm rectangle

Roughly chop the salmon trimmings (about 175g). Blend the salmon trimmings and egg whites to a purée in a food processor. Add the cream, salt and freshly ground black pepper and blend together until smooth.

Place the smaller piece of pastry onto a baking tray and spread over half of the salmon purée. Cover with the langoustines and season with salt and freshly ground black pepper.

Arrange the spinach leaves on top, then the piece of salmon. Cover with the larger piece of the pastry and crimp the edges. Trim the edges and brush with the beaten egg yolks. Score the pastry with a table knife.

Bake in the oven for 30-35 minutes, or until the pastry is cooked through and golden-brown. Set aside to rest for five minutes.

Meanwhile, for the sauce, heat a frying pan until hot and add the butter, onion, carrots, fennel and thyme and cook for 2-3 minutes, or until just softened but not coloured.

Add the langoustine shells, cayenne and tomato purée and cook for a further minute. Add the white wine and continue to cook until the volume of the liquid is reduced by half.

Add the fish stock, bring to the boil, then reduce the heat and simmer for 15 minutes.

Blend the sauce in a blender until smooth, then pass through a sieve into a saucepan. Return the sauce to a simmer, add the cream and cook for a further minute. Season, to taste, with salt, lemon juice and freshly ground black pepper.

To serve, carve the tart into slices and spoon over the sauce.