Put the fish in a heavy pan with the vinegar and water, bring just to the boil, then lower the heat slightly and simmer gently for 10 minutes.

Drain the fish and, when cool enough to handle, skin, bone and flake the flesh.

Heat the oil in a pan, add the onion and fry gently for 5 minutes until soft and lightly coloured. Add the red pepper and parsley and cook for a further 5 minutes.

Add the flaked fish, together with tomatoes, lemon juice, Tabasco, 1 teaspoon salt and a generous sprinkling of pepper. Simmer, uncovered, stirring occasionally, for a further 10-12 minutes until most of the liquid has evaporated. Transfer to a bowl, taste, adjust seasoning and leave to cool.

Roll out the pastry on a lightly floured surface to a 40 x 30 cm/16 x 12 inch rectangle.

Heat the oven to 220C/425F/Gas7.

Cut the pastry into twelve 10 cm/4 inch squares. Place a portion of the fish mixture in the centre of each square, then lightly dampen the pastry edges with cold water and fold each square into a triangle. Press the edges together, then crimp with a fork to seal well.

Arrange the patties well apart on 2 baking sheets and brush the surfaces with egg white, then prick each patty with a fork 2 - 3 times. Bake in the oven for about 20 minutes until golden brown.