Microwave the trout on a plate covered with clingfilm for
3 minutes (or steam for 4 minutes). Flake into a bowl and mix
with the rice, onion, chopped egg, zest, juice and dill. Season.
Heat the oven to 200C/fan 180C/gas 6. Roll the pastry out to
the thickness of a £1 coin on a floured surface and divide in 2
(divide the pastry first if you are short on space). Lift 1 piece onto
a buttered baking tray, spoon the trout mix into the middle
and spread to a 10 x 18cm rectangle. Wet a border around the
filling, put the other piece of pastry on top, press down around
the filling and trim the edges (use these for decoration). Brush
with glaze, cut slits in the top and bake for 30 minutes.