Leftover roast beef and vegetables - they were just asking to be re-purposed into a delectable meat pie. Here is my recipe. It is very adaptable to whatever leftovers you may have.
These are similar to Cornish Pasties, but can also be made up like pot pie in small casseroles.
Chop roast and vegetables into uniform size pieces. About 1/2-inch dice works well. Heat the meat, gravy, and vegetables together in a saucepan until heated through and gravy has reduced and thickened.
Roll out a pie crust on a floured surface and cut it into quarters. Preheat oven to 400°F.
Place 3-4 tablespoons of the meat and vegetable mixture in the center of each piece of pie crust. Be careful not to use too much. Sprinkle with salt and pepper. Fold in half diagonally, seal and crimp edges. Repeat with second pie crust.
Place pies on a foil-lined baking sheet sprayed with oil. Vent top of crust with a short slit, using a sharp knife. If desired, brush with a lightly beaten egg white wash to make a shiny crust.
Bake pies at 400°F until crusts are well-browned and crisp, about 20-25 minutes. Cool on baking sheets. May be served hot or at room temperature.
Meat mixture may also be spooned into pastry-lined ramekins and topped with more pastry. Vent, and use egg white wash if desired. Bake about 25-30 minutes until very hot and bubbly and crust is a nice golden brown.