In a large skillet over medium heat, add ground beef, breaking it apart with a spatula. Cook for 8-10 minutes until browned. Add optional diced vegetables for the last 3 minutes.

On a lightly floured surface, roll out pie dough to about 1/8-inch thickness. Cut circles of 4–6 inches in diameter.

Place dough on a clean surface, spoon filling onto one half, fold over to seal and crimp with a fork.

Preheat oven to 350°F (175°C). Beat egg with water, brush on sealed pies.

Bake on a lined baking sheet for 25-30 minutes or until golden brown.

Let the pies cool on a wire rack for at least 10 minutes before serving.