2) Preheat the oven to 230C/Gas 8.
3) Bring a large pan of salted water to a boil and cook the linguini until al dente. Drain and toss with the remaining 2 tbsp extra-virgin olive oil, then reserve.
To cook the fish:
1) Place a small square of greaseproof or waxed paper at the bottom of each paper bag. (See Cook's Note below if using waxed paper.) Place a small pile of linguini in each of the bags. Top with a spoonful of tomato sauce, making sure to moisten the linguini with the juices. Lay a piece of fish on top and arrange with another spoonful of sauce. Moisten again with juices from the sauce and season with salt and pepper.
2) Fold over the tops of the bags, place them on a baking sheet, and bake for 15 minutes.
3) To serve, transfer the bags to 4 dinner plates and let each diner cut open the package to enjoy the aromas.
Cook's Note: To make waxed or greaseproof paper "bags" fold 4 large sheets of paper in half. With the fold as the spine, cut a large semicircle (about a 20cm radius) with one end more pointed than the other (opened out, the shape resembles a heart). Open the circles. Layer the ingredients in the centre of the paper as instructed above. Leave a 2.5cm border of paper clear. Close the parchment over the fish. Starting at the flatter end of the semicircle, firmly fold the edge inwards. Fold entire edge into a series of tight, flat, overlapping pleats to enclose the fish. Fold the last pleat several times and tuck it under the bag. Put the bags on a baking sheet and bake in the oven 12 to 15 minutes. The bags will puff up and brown. Waxed paper is a nice touch to make the cooking bags because you can see the colours of the sauce through it.