Preheat the oven to 375°F (190°C).

In a large skillet or Dutch oven, heat the vegetable oil over medium-high heat. Add the steak pieces and cook until they are browned on all sides. Remove the steak from the skillet and set it aside.

In the same skillet, add the diced onions and minced garlic. Sauté until the onions become translucent and fragrant.

Stir in the frozen mixed vegetables and cook them for a few minutes until they are slightly softened.

Sprinkle the all-purpose flour over the vegetable mixture and stir to coat everything evenly.

Gradually add the beef broth, stirring constantly to avoid lumps. Bring the mixture to a simmer and let it thicken for a couple of minutes.

Stir in the milk or heavy cream and Worcestershire sauce. Season with salt and pepper to taste. Simmer for another 2-3 minutes until the sauce thickens and becomes creamy.

Return the cooked steak pieces to the skillet and stir into the sauce and vegetables.

Roll out the pie crust and place it over the filling in the skillet. Cut a few small slits on the top crust to allow steam to escape during baking.

Bake the steak pot pie in the preheated oven for 30-35 minutes, or until the crust is golden brown and the filling is bubbly.

Remove the pie from the oven and let it cool for a few minutes before serving.