A classic Cornish pasty recipe!
In a large mixing bowl, combine the flour, salt and butter using your fingertips to form breadcrumbs. Add the cold water, stir until a dough forms adding more water if necessary. Wrap the dough in clingfilm and place in the fridge for half an hour.
Preheat the oven to 220C, divide the pasty into 4 equal pieces, roll out on to a clean work surface dusted with flour.
In a large bowl, combine the onion, potato, swede and meat and season with salt and pepper. Divide the filling among each pastry, brush the edges with a beaten egg and fold the pasty over the filling so the two edges meet and crimp the edges to form a tight seal. Brush the pasties with the egg and place in the oven for 45 minutes or until golden brown.