01 -
Cook pasta in a large pot of salted boiling water according to package instructions until al dente. Drain and set aside.
02 -
In a large skillet over medium heat, cook ground beef and crumbled Italian sausage until browned and fully cooked, breaking up meat with a spoon. Drain excess fat.
03 -
Preheat oven to 190°C (375°F).
04 -
In a large mixing bowl, combine cooked pasta, browned meats, pepperoni, bacon, marinara sauce, Italian seasoning, garlic powder, and optional red pepper flakes. Mix thoroughly to distribute all ingredients evenly.
05 -
Lightly grease a 33 x 23 cm (9 x 13-inch) baking dish. Pour in the pasta-meat mixture and spread evenly.
06 -
Sprinkle shredded mozzarella, cheddar, and grated Parmesan cheese evenly over the top.
07 -
Bake in the preheated oven for 20 to 25 minutes, or until cheese is melted and bubbly.
08 -
Allow casserole to cool for 5 to 10 minutes before slicing. Serve warm.