Fruit slab

Method

1. For the pastry: sift the flour and salt into a bowl. Using your fingertips, lightly rub the margarine and butter into the flour until the mixture resembles breadcrumbs. Stir in the sugar, then add the beaten egg, mixing until the ingredients bind together to make a soft dough. Knead the dough until it is smooth, then pop it in a polythene food bag and leave it to rest in the fridge for 20-30 minutes.

2. For the filling: put the currants, mixed spice and sugar in a large pan and add enough cold water to just cover the fruit and no more. Bring to the boil and simmer gently for no more than 5 minutes, then remove the pan from the heat. Gradually add the custard paste, stirring until the fruit mixture has thickened slightly - bear in mind that it will thicken even more when cold.

3. Preheat the oven to 170C/gas 3. Grease a 30 x 18cm Swiss roll tin and line it with non-stick baking paper. To assemble the fruit slab, divide the pastry in half. Roll out one portion of pastry on a lightly floured surface and use it to line the prepared tin, pressing the pastry over the base and up the sides of the tin. Lightly brush the top edges with water.

4. Spoon the fruit mixture into the pastry case, spreading it evenly and packing it in well. Roll out the remaining pastry to a rectangle just slightly larger than the size of the tin, then lay this sheet of pastry over the filling and pat down lightly.

5. Trim away any excess pastry from around the edges using a sharp knife, then decoratively crimp the edges. Cut two slits in the middle of the top of the pie, then bake in the oven for 50-60 minutes or until the pastry is cooked and golden. Sprinkle with caster sugar while still hot, then leave to cool and serve warm or cold in slices.