Preheat your oven to 375°F (190°C). Allow pie dough to soften at room temperature for about 10 minutes. Press the dough into a deep-dish pan, prick with a fork, and pre-bake the crust for 10 minutes until lightly golden.

In a skillet over medium heat, warm a splash of olive oil. Add the ground beef and sausage, seasoning with salt, pepper, garlic powder, and Italian seasoning. Cook for 7-10 minutes until browned and fully cooked, stirring occasionally.

Spread a layer of pizza sauce over the pre-baked crust. Sprinkle half of the mozzarella cheese over the sauce, layer the cooked meat mixture on top, drizzle with more pizza sauce, and add the remaining mozzarella.

Arrange pepperoni atop the cheese layer and sprinkle Parmesan cheese if desired. Bake in the preheated oven for 25-30 minutes until the cheese is bubbly and golden brown.

Let the pie cool for 5-10 minutes before slicing. Garnish with fresh parsley before serving.