Preheat oven to 425 degrees.
Melt butter in skillet and add stew beef; cook until brown on all sides.
Add onions and continue cooking until meat is well done.
Add mixed vegetables, gravy and seasonings, mix well.
Place one pie crust in bottom of pie pan and fill with beef mixture.
Place second crust over filling, roll edges under and press down with fork.
Make 4 slits on top of crust and bake for 30-35 minutes.