Mackerel, Potato & Caramelised Onion Pasties

I found some mackerel fillets in the back of my freezer the other day, a little too freezer burned to be useful as the focal point of a dish. Loathed to throw them away I decided to cook them off and make some pasties for lunch. The addition of caramelised onion sweetens the pasties just enough to make a delicious, if rather unconventional filling. Oh, and for me the pastry must be shortcrust but feel free to use puff pastry if you are of the Ginster's persuasion. Makes three or four:

Pastry Ingredients:

Plain flour - 500g

Butter - 200g

Eggs - 2

A little milk and salt

1 extra egg for glazing, beaten

Pasty Filling:

Mackerel fillets - 6, skinned and boned

Potato - 1 large potato, peeled and chopped into 1cm dice

Onion - 1 large, peeled and very finely sliced

Butter - 25g

Veg Oil - a good splash

Method:

First make the pastry in a food processor by blitzing the butter into the flour with a pinch of salt until fully incorporated. Add the eggs and continue to process until the pastry starts to come together. Tip into a bowl and finish the mixing by hand adding a little milk if too dry. Cling and chill for 30 mins.

In a roomy pan, gently fry the onion for 30 mins in the butter and oil until deeply golden. Add the potato and on the lowest heat - covered - cook the potato until just soft but still holding its shape. Add the mackerel fillets and continue to cook stirring gently until the mackerel flakes - this should only take a few minutes. Season well and allow to cool in a colander so that excess liquid drains away. 

Roll out the pastry to the thickness of a pound coin. Cut out circles using an 8 inch plate. Place sufficient cooled filling on one half of the circles leaving a 2cm edge. You will need to use your discretion here as too much filling will make the pasties split open during cooking, too little and you will end up with joyless pasties. 

Egg wash the edge then fold the unfilled side of the pastry over to make a half moon. Roll the pasty 90 degrees so that the unsealed edge is facing upwards and crimp along the edge to seal well, shaping the pastry and distributing the filling to the edges as you go. Repeat and place the pasties on a well oiled baking sheet. Egg wash and bake at 200c for 30 mins until golden and fully cooked. I like to glaze my pasties again after 15 mins cooking so that the pastry is deeply golden and shiny.