Saute vegetables until tender. Set aside to cool.
Cut smoked fish into small pieces.
To make the white sauce, heat a pan to melt butter. Add flour to pan and cook until coloured, add a small amount of milk at a time, mixing well to make sure all is smooth. Set aside to cool a little.
Once fillings have cooled a little, in a large bowl mix all filling together and check for seasoning.
Preheat oven to 200'.
Grease and line the base of your pie tin with the flaky pastry sheet.
Fill pie tin with filling and cover with pastry sheet – for this pie we did a lattice top and little pastry shaped fish.
Bake at 200' for 10 minutes then reduce temperature to 170' and cook until golden and pastry has cooked through – this will be approximately 40 minutes.