Preheat your oven to 375°F (190°C) and grease a 9-inch pie dish.

In a large mixing bowl, combine all-purpose flour, salt, and garlic powder. Cut in cold unsalted butter until the mixture resembles coarse crumbs. Gradually add cold water to form a dough. Roll it out and press it into the prepared pie dish, then trim excess dough and blind-bake for 7-8 minutes until just set.

In a skillet over medium heat, brown the ground beef and Italian sausage for approximately 6-8 minutes until cooked through. Drain excess grease and set aside.

In the same skillet, sauté diced onion and minced garlic for 2-3 minutes until fragrant. Stir in Italian seasoning, crushed red pepper flakes, and a pinch of salt and black pepper. Add ½ cup of crushed tomatoes.

Layer half of your remaining pizza sauce on the blind-baked crust. Add half of the meat mixture, a layer of shredded mozzarella and cheddar cheeses, followed by thick-cut pepperoni. Repeat these layers and finish with a final layer of cheese.

Bake uncovered for 25-30 minutes until cheese is melted and golden brown.

Allow the pie to rest for about 10 minutes before slicing.

Serve with a side salad or garlic bread.