Preheat your oven to 350 degrees and lightly spray a 9x13 pan with non-stick spray. Set aside.
Bring a large pot of salted water to boil. Once boiling, add in your mostaccioli and cook until al dente. Drain and return to the pot.
While you're waiting for your noodles to cook, in a large skillet, over medium-high heat, add in the ground sirloin and season with salt and pepper (and whatever else you like to season your meat with). Brown the meat until fully cooked and no longer pink.
Pour the cooked meat into the pot of cooked & drained noodles.
Pour in 2 cups of red sauce, 2 cups of alfredo sauce and mix until fully incorporated.
Pour into the prepared dish and sprinkle with mozzarella cheese.
Bake for 10 minutes or until cheese is melted.