Preheat the oven to 375°F.

In a mixing bowl, combine the flour, salt, and butter until the mixture resembles coarse crumbs.

Gradually add ice water, mixing until a dough forms. Wrap the dough in plastic wrap and refrigerate for at least 30 minutes.

In a large skillet, cook the ground beef and Italian sausage over medium heat until browned. Drain excess fat.

In a bowl, mix the cooked meat with ricotta cheese, eggs, spinach, Parmesan cheese, oregano, garlic powder, black pepper, and red pepper flakes.

Roll out the chilled dough and fit it into a pie dish. Fill with the meat and cheese mixture.

Cover with additional dough, crimp edges to seal, and cut slits in the top for ventilation.

Bake for 50 minutes or until golden brown.