Creating this delightful Beef Pot Pie Casserole is simple if you follow these steps:

1. Preheat Oven: Preheat your oven to 400°F (200°C).
2. Cook Beef: In a large skillet, brown the ground beef over medium heat. Drain any excess fat.
3. Sauté Vegetables: Add the chopped onion and minced garlic to the skillet. Sauté until the onion is translucent.
4. Add Vegetables: Stir in the mixed vegetables, beef broth, Worcestershire sauce, thyme, salt, and pepper. Cook for about 5 minutes until heated through.
5. Combine with Soup: Mix in the cream of mushroom soup and shredded cheddar cheese, stirring until everything is well combined. Remove from heat.
6. Prepare Pie Crust: Roll out one pie crust and fit it into a greased casserole dish.
7. Add Filling: Pour the beef and vegetable mixture into the pie crust, spreading it evenly.
8. Top with Crust: Place the second pie crust over the filling. Trim and crimp the edges to seal. Cut a few slits in the top crust to allow steam to escape.
9. Egg Wash: Beat the egg and brush it over the top crust for a golden finish.
10. Bake: Place the casserole in the preheated oven and bake for 30-35 minutes or until the crust is golden brown and the filling is bubbly.
11. Cool: Allow the casserole to cool for a few minutes before serving.

By following these simple instructions, you’ll have a delicious Beef Pot Pie Casserole ready to enjoy!