Begin by preparing the flavorful filling. In a separate bowl, combine the ground beef, salt, black pepper, minced onion, Italian seasoning, tomato paste, and sliced mushrooms (if desired). Mix well and set the filling aside.

In a medium mixing bowl, combine the all-purpose flour, active dry yeast, sugar, and salt. Mix the dry ingredients until well combined. In a saucepan, gently heat the sour cream over medium heat. Add water and shortening, ensuring the temperature reaches 120-130 degrees Fahrenheit (49-54 degrees Celsius).

Pour the warmed mixture over the dry ingredients in the bowl. Add the egg as well. Mix the ingredients by hand until the dough becomes slightly smooth.

Grease a pie pan and spread the dough mixture into it, forming a crust. Use the back of a spoon to create an even layer. Now, it’s time to add the flavorful filling! Spoon the prepared meat mixture into the crust, ensuring it is evenly distributed. Sprinkle the shredded mozzarella cheese generously over the top.

Preheat your oven to 375 degrees Fahrenheit (190 degrees Celsius). Place the Pizza Burger Pie in the preheated oven and bake for approximately 30 to 35 minutes or until the crust turns a delightful light golden brown.

Once baked to perfection, remove the Pizza Burger Pie from the oven. Allow it to cool for a moment, but don’t wait too long! This delightful dish is best enjoyed immediately, while the cheese is still gooey and the flavors are at their peak. Slice it up and savor each mouthwatering bite.