I have made many Cornish Pasties before, using traditional recipes. They are wonderful, but a bit of a challenge if you do not do them often. I suppose that the English and Welsh housewives did them so often that they became just routine. They do use up scraps well, and you can do a thousand variations depending on what is in the refrigerator. Use any meat, being especially careful that chicken is well cooked. It is just as good to be made with a mix of meats if you have a bit of everything available. Beef, veal, chicken, pork, turkey...all would work well. The English enjoy fish pie. I confess that I know nothing of these, and how to make a good filling for them. I suppose shrimp with spinach and onions would be good. Perhaps a fish with garlic, saffron, onions and chunks of tomato would work. Take a clue from recipes like Bouillabaisse
The one drawback to using leftovers, is the extremely gentle cooking of the meat that leaves it especially tender. If the meat is precooked before it goes into the pie, it is not the same. Also, you have to remember that pork and chicken are especially good at draining the flavor out of everything. So, over-season them a bit to compensate for the extreme blandness.
All ingredients should be cold! Very cold if possible!
Measure out 10.5 ounces of flour. You really need a good scale if you are to get superior pastry. The general rule of thumb is about twice the weight of flour to butter, then add a bit more butter. You could us the pastry I have in the pie recipes posted elsewhere, but this is much better for this purpose.
Mix in 1/2 teaspoon of salt.
Cut 6 ounces of butter into very small cubes, and drop into the flour. I cut the sticks of butter into quarters the long way and then cut the long sticks up into cubes.
Using your fingers, coat all the butter cubes with the flour, tossing them with your two "claws" like tossing a salad. Continue by smearing the cold cubes of butter into the flour by pinching each one once or twice, then continue to pinch the entire mass till the butter is completely broken up and the pastry is fairly uniform. It should retain bits of butter about the size of lentils or smaller. Do not over do.
Add up to 6 tablespoons of icy cold water a tablespoon at a time. Add three, then stir with a fork. Add another tablespoon and stir again. Stop before the 6 tablespoons are in if it seems that the dough will gather up easily.
Gather the dough up into a ball, pressing it together but do not work the dough in any way. Flatten the ball slightly and put into a large plastic sandwich bag or a covered bowl or Tupperware. Set in the refrigerator for half an hour or more to allow the moisture to distribute itself evenly through the dough.
Take it out of the refrigerator and let it warm for about ten minutes.
Dust the counter with flour, rub the rolling pin with flour and dust the top of the pastry with flour.
Tap the ball repeatedly with the pin in all directions to get it to flatten into a disk.
Roll the dough out into a large 1/8 - 1/4 inch thick sheet.
Cut the sheet into quarters and line four to six tins, tiny pie plates, or ramekins. I use oval ramekins about 6 inches by four. Cornish pasties are rather long and narrow, so I guess I like the look of the oval ramekins as a result.
Press the pastry into the containers evenly leaving the rest of the dough hanging over the sides.
Fill the pastry with the cooled filling without over filling it.
Draw all the pastry over the edges and toward the middle like a drawstring bag, covering as much as possible of the filling except a space in the center to allow steam to escape. I do not take particular care with this. It looks ragged and draped rather than neat.
Brush the top of the pastry with beaten egg and bake at 400 for about 20 minutes, then reducing the temperature to about 350 till the pies are a deep golden brown and the filling is completely cooked. This could be up to another 20 minutes.
Serve hot, warm or cold. Do not refrigerate if you can help it, but if it is not going to be eaten soon, refrigerate only when completely cold. It is better to freeze it instead of refrigerating. Warm briefly in the oven when thawed.
Of course you could use anything from fruit pie filling, apples, sliced peaches or plums or meats just as described below. You could also do this with any partially cooked vegetable you like, such as a vegetable stew, eggplant and tomato chunks, pumpkin and onions, Caponata...Whatever. Caramelize a large quantity of onions then cook in a bit of tomato paste and Oregano. Mushrooms grilled till browned and mixed with caramelized onions(with or without eggs) and oregano. The Italians would use a Nepeta that grows wild in Italy, but Oregano is good too. How about braised greens like endive, dandelion, chard, Good King Henry(which you can grow in your garden as a perennial if you can find the plants) etc., mixed with onion and ham, with or without egg to bind.
I save all the trimmings from bizarre looking pork chops, the rib meat from the chicken etc. Sausage would be good and there is some interest in England in onions and bacon. Pancetta or Prosciutto cooked with Spinach, onions and olives, and feta and beaten egg added when cooled, would make a great pie.
Drop about 2 cups of meat into a food processor and chop coarsely. Some chunks should remain, but not too large.
Cube one large onion and three or four carrots.(Add potato cubes and/or , shreds of cabbage or turnip if you like, especially if you are short on meat)
Brown any meat bones you have from the trimming job you did to get the meat, in olive oil.(I try to use as much olive oil as possible instead of butter because it is much healthier. However, butter is much better tasting.) When the bones are about half cooked and nicely browned, add the onions and carrots.
Brown the veggies along with the bones, add a couple of minced garlic cloves for the last minute or two of cooking. Add water just to cover. Add a bay leaf, a rounded teaspoon of thyme and sage and a pinch of cloves if desired. Salt and pepper to taste. Simmer covered, till the veggies are nearly cooked through and the water has nearly disappeared. These pies are not meant to have a gravy like a pot pie. The regular pasties are meant to be wrapped in a napkin and taken off to be consumed in the mines or fields. Dribbling sauces would not be appropriate.
Add the chopped meat and continue to cook at a VERY low temperature, just till the pink or raw is all but gone. Less is best. If you dare, omit the cooking of the meat and let it do so in the pie instead. After all, it is in such small pieces, it should cook through without too much trouble.
Pick out the bones VERY CAREFULLY and remove the bay leaf. Then cool the filling till just warm or cold.
Spoon the filling into the pastry and top with a chunk of butter.
If you can find Quail eggs(not the most common or economical of ingredients, which spoils the economy of the recipe), soft boil and peel them, and nestle deep into the filling so they are not seen. Otherwise, if you like egg, hard boil(a little undone in the center of the yolk is best) a couple of eggs and quarter them. Nestle the quarters into the filling as you fill the pie.
Now, if you want to be absolutely correct about this, divide the dough into four or six pieces. Roll each piece into a round. Place filling in the center and fold the dough over in half. Dampen and seal the seam and crimp decoratively. Lay the pie on a cookie sheet lined with parchment, or just lightly greased. Brush with beaten egg and poke a couple of steam holes in the top. Bake as described. serve with a big dollop of Dijon or Coleman's mustard.