Preheat the oven to 350 degrees.
Spray a baking dish with cooking spray.
Cook pasta according to package directions, until al dente.
Add pizza sauce and Italian seasoning to a medium bowl and stir.
Once noodles are done, drain and add to a large bowl.
Stir in sauce.
Add 12 oz of mozzarella cheese and pepperoni, except for 15 slices to go on top. Stir until combined.
Pour into a baking dish.
Sprinkle remaining cheese on top of the pasta mixture.
Arrange 15 slices of pepperoni on top of cheese.
Bake for 15 minutes.
Remove from the oven and serve hot.