Mix the roast, potatoes, salt and pepper in a large bowl. Unroll the pie crusts and cut in half.
Put a good amount of filling in each crust, fold over, and seal.
Place each pastry on a greased cookie sheet. Make a couple of small slits in the top of each crust.
Bake for 15 to 20 minutes or until crust is golden brown.
Remove from oven and brush with some melted butter.
Serve with gravy, or if you are my Dad - ketchup.
For Beef Gravy
Bring ingredients to a boil to thicken, stirring constantly with a whisk.
*If you aren't using leftover roast, an easy way to prepare the roast is to cook it in a crock pot with 1 cup of water and an onion soup mix along with whatever seasonings you like for 3-4 hours on high or 8 hours on low. **You can also use frozen hash brown cubes. Throw them into the pie crust while still frozen. They will cook in the oven. It tastes JUST as good as using fresh potatoes.