Sift the flour. Place the flour and salt in a large bowl. Mix. Rub the butter into the flour with your fingertips until the mixture resembles breadcrumbs.
Next add approximately 1/2 of the beaten egg yolk and also add the water. Mix well your hands. Try to work quickly.
Wrap the dough in plastic wrap and chill for 10 -15 minutes.
Now take the chilled dough and roll out into a 12 inch square that is about 1/8 inch thick, using a rolling pin.
Draw a fish shape on a piece of paper and cut it out (fish should be approximately 6 x4 inch). Place the fish pattern on top of the dough and cut it out with a sharp knife. Place the pieces of fish shaped dough onto a greased baking pan (use butter or coking spray to grease the pan).
In a pan heat 1/2 tablespoon olive oil over medium high heat, add garlic and mix until slightly softened. Next add onion, salmon, and prepared (or leftover) mashed potatoes. Mix until onion is softened and everything is heated through. Add pepper and salt. Mix well.This recipe will have enough dough and filling to make 4 number of fish.
Spread your prepared filling over the pastry ‘fish’, leaving about 1/2 inch around the edges so that you can seal it. Brush the edges of the pastry with some of the beaten egg, then place additional pastry ‘fish’ over the top and press down the edges to seal. After that, you can decorate the fish with eye, mouth and scales. I’ve done in the photo above – you can use scraps of the dough and cut out small rounds and then layer them like a fish’s scales. Brush the egg on top of the pastry.
Bake about 20 minutes at 200 c degrees or until the crust is golden brown.