Posh prawn & smoked salmon pasties

Give the traditional pasty a seasonal makeover by filling it with delicious prawns and smoked salmon – perfect for a summer picnic

Simmer the potatoes in salted water for 8-10 mins or until just cooked, then drain and leave to cool. Tip all the filling ingredients into a bowl, mix well, season with a little salt and chill until needed.
To make the pastry, tip the flour, butter, lard and a pinch of salt into a bowl and work the fats into the pastry with your fingers until it makes a fine crumb. Bring 150ml of water to the boil and gradually stir into the bowl with a spatula or wooden spoon (you may not need all the water). Work the flour mixture together to form a ball, tip onto a work surface and knead the dough so it becomes smooth. Divide the dough into four balls, wrap in cling film and chill for 30 mins.
Heat oven to 180C/160C fan/gas 4. Remove a ball of dough from the fridge and roll out to a rough 18cm circle. Spoon a quarter of the filling into the middle, then draw up the edges and seal the pasty, making sure all the air has been pushed out. Crimp or fold the edges, then lay on a baking sheet. Repeat the process for the remaining three.
Brush the pasties with the beaten egg yolk and sprinkle with a tiny pinch of flaky salt. Bake for about 40 mins until golden. Remove from the oven and rest for at least 10 mins. Eat warm or leave to cool.