Roll out the puff
pastry to a thickness of 1cm/1/2in, then trim
and cut into 2 equal rectangles. Put one on a lightly greased non-stick baking tray.
Fry the
apples in the butter. When golden and starting
to soften, add the muscovado sugar and toss to coat. Remove from the heat and stir in the
sultanas, mixed peel and allspice.
Spread the
mixture on to the pastry rectangle on the baking
tray. Put the other rectangle on top and press
down lightly.
Divide into 16 squares with a
sharp knife, pressing nearly all the way
through, and brush the tops with egg yolk.
Bake
for 15 to 20 minutes. Transfer to a wire rack to
cool. Finish by dusting with icing sugar.