Cornish cowboy pasties
Preheat the oven to 180°C/350°F. Bring your butter and water to the boil in a large pan, then take the pan off the heat. Stir the flour and salt into the mixture bit by bit with a spatula, until you've got a dough. Tip it on to a floured surface and use your hands to shape it into a smooth ball. Put the ball of dough into a floured bowl, dust the top with flour, then cover with cling wrap and chill in the fridge for about 30 minutes while you make the filling.
Meanwhile, get a large pan and fry your chopped onion in a lug of olive oil for 10 minutes or until softened. Add the diced chicken and fry for 5 minutes until brown, then add the rest of the chopped vegetables and herbs. Fry for another 5 minutes, then add 3 or 4 good gratings of nutmeg. Season well with salt and pepper, then pour in the chicken stock and Worcestershire sauce. Stir in the flour and simmer on a medium heat for 15 to 20 minutes, until most of the stock has cooked away and you're left with nice thick gravy.
Dust a clean surface and a rolling pin with flour, then divide your pastry dough in half and roll each half out until it's slightly thinner than ¼ inch. Use a cereal bowl (about 6 inches in diameter) to cut 4 circles out of each half, so you end up with 8 circles. You may need to cut out 2 or 3 circles from each half first, then re-roll the remaining pastry to make the rest. Dust the circles with flour, and spoon your filling into the middle of each one. Brush the edges of the pastry with some of the beaten egg, then fold each circle in half over the filling and crimp the edges with your finger and thumb to seal them. If you want to see how this is done, check out this video on how to assemble a pasty
Line 2 baking trays with greaseproof paper, scatter a handful of cornmeal or polenta over the paper, and place your pasties on top. Brush the pasties all over with more of the beaten egg and sprinkle over a little more cornmeal. Bake in the hot oven for 30 to 35 minutes, or until golden, and serve straight away with a fresh green salad.